American Association for the Advancement of Science...

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HEALTHY PEOPLE LIBRARY PROJECT American Association for the Advancement of Science The Science Inside Obesity

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H E A L T H Y P E O P L E L I B R A R Y P R O J E C TAmerican Association for the Advancement of Science

The Scien

ce Insid

e

Obesity

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Obesity: TheScience Inside

HEALTHY PEOPLE LIBRARY PROJECTAmerican Association for the Advancement of Science

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Published 2006 by The American Association for the Advancement of Science (AAAS)1200 New York Avenue, NWWashington, DC 20005

© Copyright 2006 by AAAS

0-87168-693-7

All rights reserved. Permission to reproduce this document for not-for-profit educa-tional purposes or for use in a review is hereby granted. No part of this book may bereproduced, stored in a retrieval system, or transmitted in any form, or by any means,electronic, mechanical, photocopy, recording, or otherwise, for commercial purposeswithout prior permission of AAAS.

This publication was made possible by Grant Number 5R25RR15601 from theNational Center for Research Resources (NCRR), a component of the NationalInstitutes of Health (NIH). Its contents are solely the responsibility of the authorsand do not necessarily represent the official views of NCRR or NIH.

Any interpretations and conclusions contained in this booklet are those of the authorsand do not represent the views of the AAAS Board of Directors, the Council of AAAS,or its membership.

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INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

PART 1: WHAT IS OBESITY? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3What about fat?. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Healthy weight. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4Overweight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Childhood obesity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7The uneven impact of obesity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

PART 2: WHAT CAUSES OBESITY? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Bad eating habits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14Metabolism. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19A lack of exercise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Genetics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

PART 3: WHAT PROBLEMS CAN OBESITY CAUSE? . . . . . . . . . . . . . . . . . 25Diabetes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25High blood pressure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26Heart disease . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27High cholesterol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Stroke . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Sleep apnea . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Arthritis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30Cancer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30Societal impact . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

PART 4: HOW CAN OBESITY BE PREVENTED AND TREATED? . . . . . . . . 33Exercise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Good nutrition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Treatment methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40Diets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40Diet drugs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41Weight-loss surgery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

T A B L E O F C O N T E N T S

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PART 5: WHAT DOES RESEARCH TELL US ABOUT OBESITY? . . . . . . . . . 47Current lines of research . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47The important role of volunteers . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

CONCLUSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

APPENDIX 1: QUESTIONS TO ASK YOUR DOCTOR ABOUT OBESITY . . 57

APPENDIX 2: TAKING PART IN RESEARCH STUDIES—QUESTIONS TO ASK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

RESOURCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

BIBLIOGRAPHY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

GLOSSARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

CREDITS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

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Who wants to read any-thing else about how fatwe are? It seems like

you can’t turn on the TV withoutsomeone on the news talkingabout how much we weigh, howmuch we ought to weigh, andhow weighing too much is bad,bad, bad. It’s almost enough tomake you dig into that half gal-lon of ice cream you have in thefreezer.

It’s true that many of us doweigh more than we ought toand that weighing too much isrelated to certain health risks.That’s just a fact of life, relatedto science. Our bodies need a cer-tain amount of food to stay aliveand work properly, and extrafood can make us gain weight.

Obesity, or being too heavy foryour height, is a serious subject.It’s one of the worst chronic ill-nesses we now face. Today onlyone third of Americans weigh ahealthy amount. Two thirds ofAmericans are overweight,meaning they weigh more thanthey should and are at risk forhealth problems, including obesity. Half of all overweightpeople—and a third of allAmericans—suffer from obesity,

which can lead to serious healthproblems.

It doesn’t have to be that way,though.

We can learn why our bodies actthe way they do—what theyneed to work and what they dowith extra food we eat. We canfind out how to keep from gain-ing too much weight in the firstplace. We can learn how tochange what we eat and howmuch we exercise in order to loseweight. We can find out whathealth conditions we’re at riskfor and be tested for them. Wecan become healthier, no matterwhat we weigh.

INTRODUCTION

Jennifer Portnick, a 240-pound, 5-foot-8 SanFrancisco aerobicsinstructor, believeshealthy peoplecome in all shapesand sizes. Excer-cising will help uslive healthier lives,regardless of ourweight.

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This book will give you informa-tion about some of these things soyou can help shape your body andyour future. It will also provideresources for where you can go for more information. Write downquestions you have as you goalong. Your local librarian can helpyou look for some of the answersand point you to local resources.Your health care provider can helpanswer other questions you mighthave about your personal weightand health.

It’s good to keep in mind that obe-sity is a medical problem. Just aspeople shouldn’t be judged if theyhave high blood pressure or are

blind, they also shouldn’t bejudged because they suffer fromobesity. Chronic health problemscan be controlled. If you work tocontrol your weight, the effects onyour health—both in the shortterm and over time—will be posi-tive. Losing even a little weight ifyou are obese can have a bigimpact on your health. It is possi-ble to be healthier at any weight.

Obesity isn’t a fun thing to thinkabout. But the good news is thatobesity is treatable and that, if yousuffer from it, over time you canget down to a healthy weight. Youare in control of living a healthylife and of becoming and being thehealthiest person you can be.

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Obesity is one of thosewords that you hear usedon the news all the time.

You have a general idea of whatit means. But are you right?

Medically, someone who is obesehas more fat on his or her bodythan is considered a healthyaverage for his or her height andbone structure.

What about fat?In order to understand obesity,you have to understand fat. Butfat is another term that can beconfusing because there are twodifferent kinds: dietary fat andbody fat.

Dietary fat is a part of food. Youwant to have a little bit of fat inyour diet because it serves as amajor source of energy for yourbody. It is used to make cellmembranes and compounds inyour body that control bloodpressure, heart rate, blood clot-ting, and other body functions. Itcarries certain vitamins fromyour food throughout your body.Fat gives you healthy hair, skin,

and nails. In infants and tod-dlers, it helps the brain develop.Fat also helps you to feel full andtells your brain that it is time tostop eating. We will talk moreabout dietary fats in Part 4 onpage 33.

Body fat is a part of the humanbody and what scientists meanwhen they refer to a person’sweight or body composition. Yourbody needs to have a certainamount of body fat. It acts like ablanket to keep you warm. It

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When energyinput is equal to energy output,fat cells (lipocytes)don’t have toexpand to accomodate excess energy. It is only whenmore calories aretaken in than usedthat the extra fatis stored in thelipocytes and theperson begins to accumulate fat.

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helps to cushion you againstinjury. In certain extreme cases,stored body fat is needed as themain source of energy to keep thebody running.

But while your body does need alittle bit of fat in it, it really isn’tgood to gain too much weight.

Healthy weightThe key to overcoming obesity isunderstanding what weight ishealthy for you. But how do youfind out?

The most common way to deter-mine a healthy weight for a personis by using a tool called the bodymass index (BMI). The BMI com-pares your weight to your heightto figure out whether you are tooheavy for your height.

The BMI does not measure howmuch of your weight comes fromyour muscles compared to howmuch comes from fat, though. If, for instance, you are an athletetaking part in a sport every dayfor several hours, the body massindex cannot tell that much ofyour extra weight is in your mus-cles. For that reason, some peopleprefer to use other tools to meas-ure body fat.

Some doctors use body fat percentages to measure body fat.This method uses measurementsof weight, height, and the amountof fat on different body parts toestimate body fat percentages.

Men and women need differentamounts of fat in their body.Women’s muscles do not have thesame mass as men’s, so their bodyfat percentage is higher.

Healthcareproviders may

use devices called calipers

to estimate body fat

percentages.

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In order for the body to workproperly, men’s body fat shouldnot drop below 2% of their bodycomposition. Women’s shouldnot be less than 10%. If a per-son’s body fat percentage fallsbelow those numbers, the body will not work right and the person may have healthproblems, such as heart diseaseand infertility.

Ideally, people who exercise regularly and eat a balanceddiet will have a body fat per-centage that is neither too low

nor too high. For women, bodyfat should not be more than 25% of their total body. Formen, it shouldn’t be more than17%.

An obese person has a highamount of body fat. Women with more than 32% body fatare considered obese, as aremen with more than 25%.

Figuring out your body fat percentage uses a complicatedmath formula. Health careproviders can give you an

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Calculate your body mass index

BMI is a math problem. It is figured out by dividing your weight in kilograms by yourheight in meters (squared).

If you don’t know your height and weight in meters or kilograms, you can use theformula below to find your BMI:

Take your height in inches. ______Multiply that number by itself to find your height in inches squared. ______Take your weight in pounds. ______Divide that number by your height in inches squared. ______Multiply that number by 703 to get your BMI. _______

Let’s say you are 5’4” tall and weigh 125 pounds.If you are 5’4”, you are 64 inches tall.64”x64”=4,096 inches squared.125/4,096=0.0310.031x703=21.793

If the number is below 25, you are at a healthy weight.If the number is at least 25 but below 30, you are overweight.If the number is 30 or higher, you are obese.Free BMI calculators are available on the Internet that will do the math for you.

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estimate using calipers, or toolsthat measure body fat in an area.You also can find calculators onthe Internet. Use a calculator thatasks for at least three measure-ments to get the most accuratenumber. You may need to knowyour height, your weight, and themeasurement in inches aroundthe widest part of your forearm(the arm between the wrist andelbow), your waist, and your hips.If you are using a computer in apublic place to find out your bodyfat percentage, you may want totake these measurements at homeor in a private place like a rest-room.

OverweightBeing overweight is the middlestep between healthy weight andobesity. You are overweight if yourweight is above what is thought ofas healthy for your height. On thebody mass index, most adults areoverweight if their body massindex is between 25 and 29.9.

Being overweight is a problem in the United States. A third of alladult Americans are overweight.Seventeen percent of teenagersare overweight. Even children areaffected—19% of all childrenbetween the ages of six and 11 areoverweight.

Body fat distribution

Doctors feel that it is important to know where your fat islocated on your body. This can tell you whether you are at ahigher risk of certain health problems.

WAIST CIRCUMFERENCEPlace a tape measure around the narrowest part of your waist(probably an inch or two above your belly button). The tapemeasure should be flat against your body. You are more atrisk of having health problems if your waist measurement ismore than 35 inches if you are a woman and more than 40inches if you are a man.

BODYSHAPEDoctors feelthat it isimportant tolook at notonly howmuch bodyfat you have,but alsowhere yourbody fat isfound. If youare apple-shaped, storing extraweightaround and above your waist, you may be more at risk forobesity-related health problems than those who are pear-shaped, storing their extra weight around their hips andthighs.

WAIST-HIP RATIOThe waist-hip ratio is a mathematical way to look at bodyshape. Measure around your waist (at its narrowest point)and then around your hips (at their widest point). Divide yourwaist number by your hips number to get your waist-hipratio. For men, a ratio of .90 or less is considered healthy;women should aim for a ratio of .80 or less. If the ratio is 1.0or more, you are considered to be at risk for health problems.

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If you are overweight, you are athigh risk for obesity. And even ifyou don’t become obese, you areat a higher risk than a personwith a healthy weight of havingcertain serious health problems,particularly diabetes, high bloodpressure, high cholesterol, andheart disease. You are also moreat risk for less serious healthproblems, such as bone and jointproblems or pain, shortness of breath or asthma, and sleep disorders.

Childhood obesityObesity is not just a problem foradults. Teenagers, adolescents,and even pre-schoolers arebeginning to show signs of obesi-ty in greater and greater num-bers. Fifteen percent of childrenand 16% of teens were obese inthe year 2000. These numbersare almost four times what theywere in the early 1970s. An addi-tional 15% of children and teensare at risk for becoming over-weight.

Childhood obesity has real-timeeffects in everyday life. Childrenneed exercise and healthy foodsin order to grow and learn.

Kids who go without healthy,balanced meals during theirgrowing years are likely to suffera number of problems, including

fatigue (keeping them from con-centrating and learning) andpoor cognitive development(affecting their performance inschool). Children need a properdiet of nutritious food to stimu-late growth and to give themenergy. Breakfast is particularlyimportant to sustain a child’sability to concentrate at school.

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Fifteen percent of children are overweight.Between 26 and 41% of them will still beoverweight as adults.

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Unfortunately, children today getmuch less exercise than in previ-ous generations. While your moth-er may have walked to schoolevery day, your children now ridethe bus or in a car. Your fatherplayed stickball or tag after school;now kids play video games or areon the computer or watch TV.Many schools have tried to avoidcutting lesson time by cutting gymclasses or recess instead. Withoutproper time for exercise, childrencan become overweight. It can alsolead to problems focusing in class,

with some kids acting tired andothers being hyperactive.

In addition to problems with con-centration, childhood obesity canlead to the early onset of puberty,the period of sexual maturationwhere children’s bodies becomecapable of sexual reproduction.

Childhood obesity is also linked towhat used to be thought of asadult diseases, like type 2 diabetesand high blood pressure. The num-ber of children with type 2 dia-

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A resident of public housing inthe South Side of Chicago, IL,weeds the com-munity vegetablegarden as part ofa USDA urbanrevitalization program.

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betes quadrupled in the mid-1990s. Obese children are ninetimes more likely than childrenwith healthy weights to sufferfrom high blood pressure.

Your school nurse or pediatri-cian can help you find out ifyour child is overweight orobese. Your health care providermay use pediatric BMI charts(which are slightly different thanadult BMI numbers) to figureout if your child is at a healthyweight. Other doctors still useheight-weight growth charts,particularly with young, growingchildren, to determine whetheryour child is at a healthy weight.Doctors can use these charts tocompare your child’s height andweight to other children of thesame age and gender to makesure your child is growing andgaining weight properly.

It’s important to help obese chil-dren lose weight sooner ratherthan later. Approximately onethird of overweight preschoolerswill grow up to be overweightadults. But by the time those children become teens, their riskof remaining overweight asadults has risen to 50%.

The uneven impact of obesityObesity does not affect all people or groups alike. Accord-

ing to the Centers for DiseaseControl and Prevention, AfricanAmerican women, white men,and the poor are very likely tosuffer from being overweight or obese.

The CDC also reported in a 2005 survey that 33% of AfricanAmericans, 28% of NativeAmericans, and 26% of Latinossay they are obese compared to21% of Caucasians and only 6%of Asian Americans. If the cate-gory is broadened to includeoverweight as well as obesity,the numbers go up significant-ly—to 78% of African Americanwomen, 70% of white men, and65% of poor people.

Among children, the trendsremain true, too. AfricanAmerican girls are almost twiceas likely as white girls to beoverweight. Mexican Americanchildren’s obesity rates are morethan double those of white children. Thirty-eight percent of Native American children areoverweight.

While Asian Americans have tra-ditionally not suffered muchfrom overweight or obesity, theirchildren are beginning to catchup to other children in terms ofweight problems. The percentageof overweight Asian Americanchildren in California, the statewith the most Asian Americans

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in the United States, more thandoubled to 15% between 1994 and2003.

The problem has continued togrow worse over the last 15 years.The rate of obesity among AfricanAmericans and Mexican Ameri-cans rose by 120% as compared to50% among whites.

Economics is another reason forthe uneven impact. Millions ofAmericans cannot afford healthinsurance or expensive treatments.Health insurance pays for thingslike medicine and doctor visits.People whose jobs don’t offer themhealth insurance, or who can’tafford it on their own, often aren’table to afford to go to the doctorregularly. Without a doctor’s care,it can be harder to find out what

you weigh, find a healthy dietplan, and be screened for healthconditions that can arise frombeing obese, such as diabetes orhigh blood pressure. People with-out health insurance also oftenreceive worse care than those whocan afford to pick their doctors.People from lower socioeconomicgroups also tend to have lessnutritious diets and to be lessphysically active. Healthier foodsare often more expensive thanunhealthy foods. Often poorer fam-ilies live in areas without easyaccess to a grocery store and haveto rely on stores with feweroptions for their shopping. In addi-tion, people living in poor areashave fewer opportunities to liveactive lifestyles due to safety con-cerns and fewer parks or low-costgyms.

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Childhood Obesity— A Growing Problem

Growing up as an overweight kid in MexicoCity, Mexico, Norell Rosado was the pictureof health—at least in his mother’s eyes.

Now, as a pediatrician who works withoverweight children and their parents,Rosado knows his mother isn’t alone in herdesire to raise robust kids. “There’s this per-ception, especially in the Latino community,that being plump means a child is healthy.The problem is that if a child is overweightwhen they are 18–24 months, chances arethey will be obese as an adult.”

Rosado is a classic case in point. He enteredlife as a heavy baby and the pattern contin-ued throughout childhood. It’s easy tounderstand why: growing up, he had tolook no further than his family’s pantry forhigh-calorie sweets and snacks. Mealtimesmeant big portions of foods high in fat andcarbohydrates, and desserts were a dailypart of his diet, as was a nighttime snack ofsweet bread.

As a college student and as a medical resi-dent, Rosado continued making unwisefood choices—a practice that would resultin his weight ballooning to more than 200pounds, about 20% more than the idealweight for his 5’9” frame.

After residency, Rosado began working atthe Pediatric Obesity Clinic at Mount SinaiHospital in Chicago, Illinois, where he coun-seled families about the dangers of obesity.It was a subject that hit too close to home.So several years ago, at age 30, he decidedhe had had enough. “Here I was counselingparents about the dangers of being over-weight, and I was heavy myself,” Rosadoadmits. Rosado dropped 45 pounds, but noteveryone was pleased. “My mother contin-ues to call me asking if I’m still skinny,”

Rosado says with a chuckle. “She worriesthat I don’t eat enough.”

Of course, it’s the extra pounds, especially inchildren, that should cause alarm.Coinciding with the rise in childhood obesi-ty has been a frightening increase in type 2diabetes in children. Obesity can also leadto heart disease, liver disease, high bloodpressure, and joint problems. Not inciden-tally, obesity in children can also affect theirself-esteem.

Because of the dangers associated withchildhood obesity, early intervention andfamily support is critical, says Rosado, whoworks predominantly with the Latino com-munity. He begins educating parents aboutproper nutrition when their baby is aboutnine months—the age when table food istypically introduced. If the wrong foods areat the dinner table, the child is in trouble.

The problem is that parents often believelong-standing nutritional myths, includingthat fruit juice and sports drinks, whichoften contain lots of sugar, are nutritious,and that a child can never consume toomuch milk. These beliefs and others likethem have contributed to childhood obesityin the United States doubling over the last10 years, with one child in nine being con-sidered far beyond the healthy range.

By working together on food selection, por-tion control, and exercise, Rosado believesfamilies can achieve their weight loss goalsand help ensure a healthier future.“Children cannot lose weight on their own.They need a parent who can help themmake smart food choices and who willencourage them to exercise.”

And for overweight kids who feel that ahealthy weight is a struggle that can’t bewon, Rosado is living proof to his patientsthat it can.

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Part 2: What Causes Obesity?

When peoplehad to farm toget food to eat,they used up asmuch energy tobring food tothe table asthey got fromeating thatfood.

Now that we know whatobesity is, we can askwhat causes it? If being

overweight is such a bad thing,why are so many Americans soheavy?

A long time ago, when food washard to find, people had to workhard to eat. Some people werehunter-gatherers, and they hadto chase animals around to catchthem for food. Other people hadto move from place to place asthey gathered up all theresources in each spot or as the animals they were huntingmoved on. Other people werefarmers and they had to workhard in the fields to make thingsgrow. Either way, people used upa lot of energy to bring food tothe table. Food was used as afuel (the way you put gas in acar to make it go). Any food thatwasn’t burned up right away inyour daily activities was storedby your body for times when itwould be harder to find food, likewinter or times of drought.

Over time, though, the way weget food has gotten easier. Mostof us don’t need to hunt wild ani-mals or gather berries in thewoods for our dinner. And veryfew of us live on farms where wehave to take care of our animalsor work in the fields.

Today most of us hunt for food inthe grocery store and gather itoff the shelves. We live in places

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where we drive or take publictransportation to the grocerystores. We buy food that someoneelse has made. Often times, wejust have to pop it into themicrowave, and we don’t evenhave to work in the kitchen tohave a meal.

While this is really good for letting us do other things we’d

Why do our bodies store energy?

Back when humans were hunter-gatherers (whichseems long ago, but was for most of the time thathuman beings have existed), their very time on earthdemanded they be active in order to follow theirprey or to gather fresh fruit, grains, and vegetables.Because these people were always traveling, theycould only hunt or gather what they could carrywith them. There was no point in taking more thanthey could use, because it required too much workto take with them.

To survive long winters, the human body evolved. It stored any excess energy in fat cells so it coulddraw on that resource when new energy sourceswere hard to come by (like a savings account or arainy day fund). So if there wasn’t any food to eatone day, the body could use up spare energy it hadstored in the fat cells. Eventually, the body wouldeither find new energy, or it would use up the energy the body had stored and would die.

Later (about 10-12,000 years ago), people began tofarm. This also required a lot of energy, so peoplewere still very active. However, they had stoppedtraveling so much, so they were able to save extrafood for when times were hard. They didn’t have torely as much on their own personal ability to saveextra calories for later. Because they were still usingup lots of energy just to exist, though, obesity wasstill rare.

Nowadays, food is readily available almost every-where in the developed world. We tend to stay putmuch more, and time- and energy-saving machineshave made it so that even if we work a job thatrequires a lot of physical activity, we don’t use up asmuch energy as our ancestors did. Society hasevolved to make life easier, but our bodies stillbelieve we should be hunter-gatherers and are out-dated in terms of the need to store spare energy.

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rather spend time on, it’s not howour bodies are meant to work.

Bad eating habitsNatural and healthy foods arebest for the human body. But let’sface it; few of us actually eat onlyfoods you can find in nature.These days, it’s actually hardwork to find, prepare, and eatonly those foods. It’s much easier(and cheaper!) to find a candy baror a soda at the local corner mar-ket than it is to buy an apple or acup of yogurt.

For most of us, eating unhealthythings every once in a while won’thurt us. What will hurt us iswhen we eat them regularly.

The main link between our eatinghabits and obesity is how muchfood we eat. Back when peoplewere farmers or hunter-gather-ers, they didn’t have easy accessto food and so people ate smallportions and few meals a day. As it became easier to get food,people began eating more mealsand bigger portions.

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In fact, even over the last 30years, portions have gotten bigger.Twenty years ago a bagel wasthree inches in diameter and con-tained 140 calories. Today’s bagelis twice that size and contains 21/2times the calories. And at fast foodrestaurants and movie theaterstoday the small-sized soda is thesame size as our parents’ largesize.

But just because times (and por-tion sizes) have changed doesn’tmean the body’s way of reacting tofood has.

The basic unit of energy in food iscalled a calorie. All the foods youeat have different amounts of calo-ries. But one calorie in one food isequal to one calorie in anotherfood. And a calorie of protein is thesame as a calorie of fat. In otherwords, a chocolate cake calorie isthe same as a collard green calo-rie. (Chocolate cake has a lot morecalories than collard greens,though!)

After you eat food, it moves to thestomach to be digested.

All the activities you take part inuse up different amounts of calo-ries or energy. Even the thingsyour body does that you don’t haveto think about—growth, thought,movement, breathing—use up

energy.

The body works best when it has a balance between what goes intothe body and what the body putsout. In other words, you should tryto eat about the same number ofcalories your body will use up.How many calories we usedepends on three things:

1. How much muscle we have.Our muscles use energy all thetime, and they use up themajority of the calories weshould put into our body.

2. How much we weigh. It takesenergy to move each poundfrom place to place.

3. How far we go. Moving ourbodies takes energy. Walkingrequires more energy thanstanding still because we moveour bodies over a distance.Running for 10 minutes usesmore energy than walking 10minutes. But running twomiles and walking two milesuse up almost the same amountof energy because you havetraveled the same distance.

Most of us, though, tend to put inmore calories than we use up. Weeat big portions, or we snack onfoods that are high in calories, orwe eat all the time. In fact,Americans tend to eat 3,800 calo-ries a day—nearly twice the aver-age amount we should.

HIDDEN SUGARS

Sugars are oftenhidden in thelabels of foods.While you maysee sugar listed in the ingredi-ents, you shouldalso look forthese “hiddensugars”:

Corn syrupHigh-fructose

corn syrupFruit juice

concentrateHoneyMolassesBrown sugarDextroseFructose

(sugar found in fruit and fruit products)

GlucoseInvert sugarLactose (sugar

found in milkproducts)

MaltoseMalt syrupMaple syrupRaw sugarSucroseSyrup

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When we consume more caloriesthan our body can use up, thebody thinks we are trying tostore those calories for later andconverts them into fat cells. Onepound of fat is only 3,500 excesscalories. (You have to use up anadditional 500 calories abovewhat you consumed every day ofthe week just to lose one pound!)Store too many extra calories andhave too much fat, and you’re atrisk of becoming overweight orobese.

Our bodies need certain kindsof nutrients in our foodbecause they provide importantthings to keep us healthy. Weneed proteins (made up ofamino acids) to grow, buildand keep up the body's organs,tissues, and muscles, and tohelp with digestion. We needcarbohydrates, which provideenergy. We need certain typesof dietary fat to grow anddevelop as babies, to insulatethe body, to create some hor-

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mones, to absorb some vitamins,and to have healthy hair, skin,and hearts.

In addition to just plain eating toomuch, we also eat too much of the wrong things, in particularsugar and fats. Americans have asweet tooth. We start the day withsugary cereals. We like desserts.We eat lots of sweet snacks.

Sugar is a carbohydrate, as arestarches and fiber. (The word “car-bohydrate” is sometimes shortenedto “carb.”) Carbohy-drates provideenergy for the body, especially thebrain and the nervous system. Theliver breaks down all carbohy-drates into glucose (blood sugar),which the body uses for energy. There are two types of carbs: sim-ple and complex. The body process-es simple carbs quickly. Thosefound in nature, such as fruits andfruit juices, milk products, andsome vegetables, can be a quicksource of healthy energy for yourbody. Refined sugars, such as tablesugar, candy bars, and soda, arenot healthy. They are also simplecarbs, but while they provide calo-ries, they don’t add anything elseyour body needs, like vitamins,minerals, or fiber.

Complex carbohydrates, found infoods like beans, whole grain breadand cereal, and starchy vegetablesgive your body not only caloriesbut also vitamins, minerals, and

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Cholesterol

Cholesterol is a soft, waxy substancefound in all areas of the body, includingthe heart, liver, intestines, muscle, skin,and nervous system. It is produced bythe liver and derived from animal-basedfoods (like meat, eggs, and butter) inthe diet. Its job is to help form cell mem-branes, some hormones, and vitamin D.

There are two types of cholesterol:“good” and “bad.” “Bad” cholesterol(LDL) flows from the liver to the rest ofthe body. When there is too much LDLcholesterol in the bloodstream, some ofit can stick to the inside of the arteries,causing a buildup of plaque and ham-pering the flow of blood. This can leadto stroke or heart attacks. It is recom-mended that people maintain blood lev-els that are low in “bad” cholesterol andrelatively high in “good” cholesterol.“Good” cholesterol (HDL) flows back inthe blood from the rest of the body tothe liver. It helps blood vessels and theliver to clean up and eliminate excesscholesterol.

The healthiest levels of cholesterol are:Total cholesterol: Less than 200LDL: Less than 100HDL: Greater than 40

Your health care provider can tell youyour cholesterol levels after drawingsome of your blood and testing it.

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fiber. They take longer for theliver to break down and leave youfeeling full longer. (Foods likewhite bread and white rice havebeen processed, contain less fiberand more simple sugars, and willnot keep you feeling full for aslong.)

The other things we tend to havetoo much of in our diets are thebad kinds of fat. We eat foodsthat are cooked in animal-basedfats (butter or lard). We eat fattycuts of meat. We eat ice creamand put half-and-half in our coffee.

There are four different types offats in our diet. The first two areunsaturated fats (monounsatu-rated fats and polyunsaturatedfats) and are found in olives andolive oil, most nuts, avocados,fish, and most liquid cooking oils,such as corn and soybean. Thesetypes of fats give us a good bal-ance of cholesterol in our blood-stream.

The fats that increase our badcholesterol levels are saturatedfats and trans fatty acids.Saturated fats are found in wholemilk and other dairy products,

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Digestion, circulation, and wasteelimination

are all part ofmetabolism.

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red meat, chocolate, and coconuts.Trans fatty acids are the fats thatwere invented in order to eat lesssaturated fat and to give foods alonger shelf life. They are theworst type of fat you can eat, and you should try not to includethem in your diet. Trans fatsinclude partially hydrogenatedvegetable oil, vegetable shortening,and most margarines. They’refound in anything deep-fried, likefrench fries, and many other fastfoods, as well as most baked goodsyou buy at the store (and at manybakeries).

MetabolismThe chemical processes of main-taining and sustaining your bodyare called your metabolism.Metabolism includes digestion,waste elimination, breathing, circulation, and temperature

regulation. By the time adultsenter their 30s, their metabolismnaturally begins to slow and thebody becomes less efficient at pro-cessing calories. This slowdowncan be reduced, however, by increasing muscle buildingexercise and physical activity.

A lack of exerciseAs we’ve already talked about,your body works best when it isusing up the same number of calo-ries you’re putting into it. Thosefarmers and hunter-gatherers usedup a lot of energy getting theirfood and preparing it. Today, welive a very sedentary lifestyle. In other words, we don’t get upand move enough.

Technology and modern life havemade things very easy for us. Wehave remote controls for our TVs

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This much food Contains this That you will have to do this muchmany calories exercise to use up*

1/2 cup carrots 25 calories 5 minutes of grocery shopping

4 oz. unsweetened juice 60 calories 15-minute stroll

1 medium egg 75 calories 15 minutes of playing Frisbee

1/2 English muffin 80 calories 11 minutes of gardening

1 cup fat-free milk 90 calories 27 minutes of ironing

1 ounce cheddar cheese 115 calories 12 minutes of housecleaning

1 12-ounce can of cola 160 calories 35 minutes of weight-lifting

1 croissant 235 calories 37 minutes of swimming

1 hamburger 245 calories 30 minutes of working out at the gym

1 pan-fried pork chop 335 calories 38 minutes of half-court basketball

1 cup chili con carne with beans 340 calories 45 minutes of raking leaves

1 cup potato salad made with mayonnaise 360 calories 30 minutes of touch football

1 cup moist bread stuffing 420 calories 31 minutes of stair climbing

1 slice pecan pie 520 calories 58 minutes of shoveling snow

1 cup oil-roasted peanuts 840 calories 81 minutes of soccer

*These figures are approximate and are based on a 200 pound person exercising at a moderate level. Someonewho weighs less will use up fewer calories during the same time period.

How to exercise off your food

and our stereos so we don’t haveto get up to change the channel.We can pop food into the micro-wave and go watch TV while din-ner cooks instead of standing inthe kitchen for hours. We candrive or ride public transportationinstead of walking to work, school,

or the shopping center. We sit infront of computers, TVs, or videogames all day. We ride elevatorsto get to our apartments or officesinstead of taking the stairs.Thestatistics are stunning. Nearly38% of all Americans get no exer-cise at all. Nearly 55% of Native

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Americans, 52% of Latinos, and50% of African Americans reportthat they are inactive. People whohaven’t graduated from highschool and who lack a GED areeven worse off—61% of them getno exercise—as well as 55% of poorpeople. People who live in the cityget more exercise than people out-side a city area. Geographically,Southerners are 8% less activethan people in the rest of the coun-try. The good news among thenumbers? Without exception, peo-ple are slowly becoming moreactive.

Sometimes we don’t get enoughexercise by choice. We choose totake the elevator instead of thestairs. We prefer watching TV to going outside to the park.Other times, things that are out ofour control make getting exerciseharder. We live in a town wherethere are no sidewalks. Our neigh-borhood is dangerous and kidsshouldn’t play outside. We have ahealth condition that makes ithard to exercise. We can’t find thetime to exercise between workingtwo jobs. (Some low-cost ways tofit in exercise can be found in Part4 on page 36.)

GeneticsHealth research has shown thatgenetics is linked to obesity andthe health conditions it can cause.

Genetics is the field of science thatlooks at how genes are passeddown from one generation toanother to influence traits.

Some people have a genetic pre-disposition to a certain disease if there is a history of the diseasedeveloping in members of theirfamily or in people from theirsame ethnic background.

Obesity seems to run in families.Some of that can be attributed tosimilar lifestyles and eatinghabits. But not all of it. Forinstance, while having two obeseparents makes a child six timesmore likely to become obese him-self, having only one obese parentstill makes a child twice as likelyas children of non-obese parents tobe obese.

Genetics works in other ways, too.Fat cells produce an appetite-con-trolling hormone, leptin, which issupposed to tell the brain that thebody is full. When you have fewerfat cells, less leptin is producedand the brain believes it needs to eat. Most obese people havehigher leptin levels than average,which should mean that their bod-ies don’t want to eat. But some-where in their bodies, the messagefrom the leptins gets lost. Scien-tists think that a person’s genescould cause this malfunction.

OBESITY AS A SYMPTOM

Mild or evenmoderate obesity canalso be asymptom of certainhealth conditions. If you know you have one of thesehealth conditions (or if you suddenlygain weightfor no obvious reason), you shouldtalk to yourdoctor:

• Thyroid disorders

• Cushing’s syndrome

• Hormonalimbalances,such as polycystic ovary syndrome

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Obesity can run in families. If you have overweight relatives, you might be at risk, too.

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A Losing Proposition for Life

Somethingstrange hap-pened whenAdona Leonardturned 25 yearsold. Her waist-band began topinch. A roll offlesh appearedthat wasn’tthere a yearearlier. Herface became

fuller, as did her arms, legs, and hips.

Her body—always lean in spite of beingraised on southern cooking—was suddenlystoring fat in ways it never had before.Seemingly overnight, Leonard packed on 30extra pounds.

“I tried dieting, and I lost a few pounds, butI wasn’t really committed to losing weightuntil my mother died when she was only 59years old,” explains Leonard, a stylishwoman with a bright, vibrant smile. “That’swhen it clicked: I had to be healthy or Iwould follow in the footsteps of my momand the other women in my family.” Thewomen in her family, Leonard says, tend tobe overweight and suffer from a host of serious health conditions, including diabetes and high blood pressure—life-threatening conditions that often come with being overweight.

With a steely resolve that came with know-ing that she wanted to live a long and fulllife, Leonard joined a national weight lossprogram that focuses on eating nutritiousfoods, exercise, behavior modification, andemotional support. It wasn’t her first timejoining the program, though for her, thethird time really was the charm.

“I wasn’t so concerned about the numberson the scale. In fact, it took me a year to loseall the weight that I wanted,” Leonard says.“Losing weight slowly didn’t bother mebecause I knew that I wanted to make long-term changes that would result in my beinghealthier.”

For instance, Leonard used to think a plateof collard greens and other vegetablesdrenched in butter and flavored with hamhocks was an example of healthful eating.“After all they’re vegetables, right? A lot ofpeople are like that. They think they are eat-ing well, but they don’t know what they are really putting into their bodies,” saysLeonard.

After a year of faithfully attending weight-loss meetings, walking on a treadmill athome, and breaking a lifetime’s worth ofbad eating habits, Leonard’s waistbandstopped pinching: She’d lost 28 pounds.

Still, three years after reaching and main-taining her goal, Leonard still attends severalweight loss meetings a week and even totesa portable scale with her to many of themeetings. That’s because instead of attend-ing the weight loss meetings, she is leadingthem.

And she’s doing it with more than a pinch ortwo of humor, an extra serving of enthusi-asm, and a healthy portion of encourage-ment.

“Who’s a ‘big loser?’” she asks at the start ofmany of her meetings—held throughoutMontgomery County, Maryland. To Leonard’ssheer delight, a number of people proudlywave their hands.

If they continue their winning ways,Leonard—no doubt—will be seeing a lot lessof them in the future. And that would keepa smile on her face.

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Why is obesity such a bigdeal, you might ask.Most of us, after all,

carry around a little extraweight or would like to be a littlethinner. What’s it hurt if we gaina few pounds?

You might be surprised to knowthat it can hurt—a lot. Five outof the top ten chronic diseasesare related directly to over-weight and obesity. They canlead to some of the deadliest pre-ventable health problems outthere—diabetes, heart disease,high blood pressure, high choles-terol, stroke, and even cancer. Inaddition to those major healthproblems, diabetes has also beenlinked to a number of less severebut still chronic health condi-tions including arthritis.According to the leading Britishmedical journal, obesity has evenbeen linked to premature aging.Being obese can make your bodythink you’re up to nine yearsolder than you actually are!

In addition to the impact on ourown health, obesity affects socie-ty and those around us in gener-

al through the higher cost ofhealth care. Let’s look at some of these problems in more depth.

DiabetesOverweight and obesity are keytriggers for type 2 diabetes.

Glucose is a form of sugar foundin food. When the body digestsfood, glucose moves into thebloodstream. In response thebody is supposed to release a

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Part 3: What Problems CanObesity Cause?

When thebody’s cellsdon’t reactright toinsulin, it is a conditionknown as diabetes.

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hormone called insulin. Anorgan called the pancreas releas-es insulin, and it triggers theopening of body cells so glucosecan enter and be used for energy.

When the body’s cells resist theaction of insulin, this is known asinsulin resistance and is thecause of type 2 diabetes. Diabetesis a chronic disease, so while it canbe prevented and controlled, itcannot yet be cured.

If glucose doesn’t move into thecells, too much stays in the blood.This makes a chemical imbalancein the body which increases thefats in the blood and which candamage the blood vessels, thepipelines through which bloodtravels to all parts of the body.

Diabetes is a serious conditionalone, but it can also lead to otherhealth problems if it isn’t con-trolled, including blindness, heartdisease, stroke, pregnancy compli-cations, kidney disease, and circulation problems that can leadto amputations.

Carrying extra fat appears to trig-ger insulin resistance, thoughresearchers do not yet understandwhy. What they do know is thatmore than three-fourths of all peo-ple with type 2 diabetes are over-weight or obese.

Early findings from the DiabetesPrevention Program suggest thatfor those people who are at highrisk for diabetes, there is somebright news on the horizon. Withintensive lifestyle changes consist-ing of diet and exercise, over-weight people who lost five percent of their body weight andwho exercised moderately at least30 minutes a day, reduced theirrisk of getting type 2 diabetes by58 percent.

People who already suffer fromdiabetes can also improve theirhealth by losing 10% of their bodyweight. By losing weight, you helpcontrol your blood sugar levels,which, in turn, can lower theamount of medicines you need to take.

High blood pressureObesity is a key risk for highblood pressure (also calledhypertension).

Every time your heart beats, itpumps blood through arteries,exerting pressure (or force) on theinside of your blood vessels. Thisis called blood pressure. Normalblood pressure is below 120/80.(The two numbers reflect themeasurements of the pressure inthe arteries when the heart ispumping and when it is resting.)

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If the pressure caused by theblood on the arteries is too high,it is known as high blood pres-sure. If this condition isn’t treat-ed, it will cause damage to thearteries and put strain on theheart. This can lead to serioushealth problems, including heartdisease, stroke, kidney failure,and blindness.

When a person gains weight, hisor her blood levels also increase,causing the heart to pump moreblood. The additional weight alsocan cause a person’s blood pres-sure to rise because it canincrease cholesterol levels, whichmay lead to a further strainingand hardening of the blood ves-sels and heart.

Losing weight helps lower bloodpressure. Losing just 10 poundsif you are overweight will help tolower your blood pressure sever-al points. The more weight youlose, the lower your blood pres-sure will be. In addition to that,modest weight loss, with or with-out lowering the amount of sodi-um you consume, can lower yourrisk of developing high bloodpressure by up to 20% if you areoverweight and at high risk ofdeveloping the condition.

Heart diseaseObesity and its complications are among the top risks for heart disease.

Heart disease is a term used todescribe a variety of illnesses in

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which the heart doesn’t work orpump right. It is caused by thenarrowing of the arteries that feedthe heart.

Heart disease causes about 40% of the deaths in the U.S. People whoare obese or overweight are twiceas likely to develop heart diseaseand are much more likely to diefrom it.

The risk of heart failure increasesfor each additional point of a per-son’s BMI (4–8 pounds). For men,their risk increases by 5%; for

women by 7%. Similarly, losingjust 10% of your body weight canreduce your risk of developingheart disease by improving howyour heart works and loweringyour blood pressure and choles-terol.

A diet high in saturated and transfats has been shown to lead toheart disease.

Seventeen percent of the total costof heart disease, $8.8 billion, isrelated to overweight and obesity.

Reduce your sodium levels, too!

In addition to the unhealthy ways we eat that contribute to obesity, we also have too muchsodium into our diets. While this is not a direct cause of obesity, it does contribute to otherhealth problems, like high blood pressure and heart disease.

You should not have more than 2,300 milligrams of sodium a day in your diet. This is aboutthe amount of salt in a teaspoon. A better amount to aim for is 1,500 milligrams of sodium aday.

Most Americans eat two to four times that amount every day. Some of that sodium comesfrom salting our food when it’s cooking or when it gets to the table.

Most of it, though, is hidden in the food before it gets to us. Processed foods (food that ismass-produced or that is changed before it gets to us) contain salt or salt products to givethem more or a different flavor or to give them a long shelf life. That means that instead ofthe food spoiling quickly, the way it would in nature, it stays fresh on the shelves of your gro-cery store. Salt is also found in many flavorings.

Processed foods that are high in sodium include frozen dinners, canned foods, catsup, potatochips, and rice blends (as opposed to rice without flavorings added to it). Other foods thatare high in sodium include cured meats, such as ham, and pickled foods, such as dill cucumberpickles.

Lower the amount of sodium you have in your diet by eating fresh foods. Frozen vegetablescontain less sodium, but if you prefer canned vegetables, make sure you rinse them beforeyou cook them. Use lemon, herbs, or spices to season your food instead of table salt.

A little bit of salt in our diets is okay. But when we only eat foods that come out of boxes orbags, we’re getting more salt than our bodies can handle.

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High cholesterolBecause overweight and obesepeople often eat diets high in sat-urated and trans fats, they oftenhave high cholesterol levels.Roughly a quarter of those whoare overweight or obese havehigh cholesterol.

High cholesterol is a risk factorfor stroke and heart disease.

Eating less saturated fat, avoid-ing trans fat, and increasing theproportion of unsaturated fatsand fiber in your diet can lowercholesterol levels.

StrokeObesity is a risk factor for astroke as well.

A stroke is what happens whenan artery carrying oxygen to thebrain bursts or becomes blockedby a blood clot or some other par-ticle. The brain doesn’t getenough oxygen and its nerve cellsbegin to die. The nerves in thebrain control different parts andfunctions of the body and if thenerves die, then those parts orfunctions don’t work right.Obesity can cause the risk factorsfor stroke—high blood pressure,diabetes, high cholesterol levels,and heart disease—as well asbeing a risk factor itself. Stroke is the number three killer amongall diseases.

As mentioned earlier, losingweight seems to have a directimpact on lowering blood pres-sure, which is a key risk factorfor stroke.

Sleep apneaObesity, particularly in the upperbody, is the main risk factor forobstructive sleep apnea.

Obstructive sleep apnea is acondition in which a person regu-larly stops breathing while asleepbecause of an obstruction in theairway. It can lead to fatigue dur-ing the day and difficulty withlogical thinking skills.

People who are more than 100pounds overweight are 12–30times more likely to have sleepapnea. About 7% of obese chil-dren suffer from sleep apnea.Two thirds of the people withobstructive sleep apnea areobese.

A girl adjuststhe straps onthe mask shewears at nightto treat hersleep apnea.

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Obesity also contributes to othersleeping disorders, including day-time sleepiness.

Losing weight can help to improvethe symptoms of this condition.

ArthritisObesity has been linked to osteo-arthritis and gout.

Arthritis is pain, swelling, andstiffness in the body’s joints, whichcauses permanent damage to thejoints. Osteoarthritis is the mostcommon kind of arthritis and usu-ally affects older people. Obesitycan cause it to happen earlier.Obesity particularly affectsosteoarthritis in the hands, hips,back, and knees. It is possible bothto keep osteoarthritis in the kneesfrom getting worse and to get ridof symptoms of the condition bylosing weight.

Gout occurs when too much uricacid builds up in the body, leadingto the development of needle-likecrystals in the joints (particularlythe big toe), uric acid under theskin, and kidney stones. Beingoverweight is linked to goutbecause there is more tissue in the body and more uric acid. An increase in uric acid also canbe related to eating a diet heavy incertain foods, including alcohol ororgan meats such as liver.

Weight loss can lower the stress on knees, hips, and back and canimprove the symptoms related togout and arthritis.

It should be noted that if you havesuffered from gout before, youshould talk to your doctor beforebeginning a diet. Some dietsincrease uric acid in the body for aperiod of time, and this can lead toa flare up of the condition.

CancerObesity is a risk factor for severaltypes of cancer. They include post-menopausal breast cancer, kidney cancer, esophageal cancer,colorectal cancer, and endome-trial cancer. Obesity and a lack ofphysical activity may account for25–30% of these cancers. Somestudies have reported linksbetween obesity and cancers of thegallbladder, ovaries, and pancreas.Other cancers—including of theliver, stomach, prostate, andcervix—have a higher death ratefor those with a higher BMI.

Women who gain nearly 45 poundsafter age 18 are twice as likely todevelop breast cancer. Almost halfof post-menopausal women areobese.

Men who are morbidly obese havecancer death rates that are 52%higher than their non-obese peers;women’s rates are 62% higher! It

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is estimated that obesity could belinked to as many as one fifth ofall cancer deaths.

Information about how exerciseimpacts cancer rates is lacking,but recent studies suggest thatgetting regular moderate exercisecan lower colon cancer risk.Further studies are necessary tomake a definite link, though.

Societal impactObesity has a very real cost tosociety in terms of its directhealth care costs: $61 billion.

Among children and teens, annu-al hospital costs related to obesityhave more than tripled over thelast 20 years, now reaching $127million.

According to some estimates, by2020, one fifth of all health caredollars spent on adults ages50–69 will be on obesity-relatedmedical problems, double what itwas in 2000. The obesity-relateddisability rate of that group alsowill grow by about 20%.

In addition to health care costs,obesity leads to lost productivity.More than 39 million workdaysare lost every year due to obesity.

The good news is that the samesteps you take to lose weight (eat-ing a healthier diet and exercis-ing) also are steps to loweringyour risk of many of these healthproblems. By changing yourlifestyle, you are protecting your-self from some very serious condi-tions at the same time.

Part 3: What Problems Can Obesity Cause?

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Obesity is a riskfactor for manytypes of cancer. It also seems tolower the survivalrate of some cancer patients.

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Thinking Beyond the Waistline

To women whothink that goodhealth can bemeasured solely bythe size of theirwaist or a numberon a bathroomscale, Dr. D. LeeAlekel, an associ-ate professor ofnutrition at IowaState University,cautions thatweight is just part

of the equation to good health.

Her assertion is based on 20 years of scientif-ic research showing a strong link betweennutrition and physical activity and overallhealth in mid-life women. It is also a find-ing—like so much scientific inquiry conduct-ed in labs across the country—that comesfrom her personal commitment, determina-tion, and sacrifice.

“It’s difficult to have balance in life,” saysAlekel. “As a researcher and a professor, it’snot unusual to put in 15-hour days. I do itbecause I have always had a strong interestin science and nutrition, and I think it’simportant to help people lead healthierlives.”

On the Iowa State University campus, sheattempts to do that on a number of fronts:She instructs undergraduate students, teach-es graduate courses, helps those working ontheir graduate degrees, serves on profes-sional committees, gives talks in the commu-nity, and works with women who volunteerto take part in research. And if that werenot enough, she writes proposals seekinggrant money so that scientific research cancontinue.

“It’s never-ending,” Alekel says with a laugh. But, she adds in a matter-of-fact way,“That’s how it is.”

Alekel, who developed her love of biologyin junior high school, does get satisfaction inknowing that women today are more healthconscious than their mothers.

Specifically, Alekel believes that morewomen today, particularly those with chil-dren, are acknowledging and accepting thatgood health depends on making smartchoices with both nutrition and exercise inmind. “Women are tending to think beyondtheir waistline. They understand that thechoices they make today will affect theirhealth and quality of life in their lateryears.”

Unfortunately, too many women, particular-ly those who are younger, still make dietaryand exercise choices based on a concernabout outward appearance. To this, Alekelwarns, “Sharply reducing fat intake andcalories simply is not the answer. The con-cern should be about what is going on inthe inside, not just how you look on theoutside.”

Fruits and vegetables, whole-grains, fiber,and other cancer-fighting antioxidants areamong the categories of foods that Alekelrecommends as part of a well-balanced diet.Good nutrition—combined with exercise—can make a profound impact on preventingbreast cancer, osteoporosis, obesity, andother diseases and disorders that affectwomen at a disproportionately higher ratethan they do men. Importantly, cardiovascu-lar disease, a leading killer of both men andwomen, can also be prevented throughnutrition and exercise.

Alekal’s approach—a blend of moderateexercise and a balanced diet—is simple, yet tried and true.

But with the busy lives that most womenlead, is it really possible to eat smart andexercise regularly? Alekel, who is also theproud mother of a 10-year-old boy, is proofthe answer is yes. “I guess I’m lucky; I reallylike healthy foods. It is difficult to maketime for exercise, but I do try to make timeto bicycle and walk, particularly in niceweather.”

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Part 4: How Can Obesity BePrevented and Treated?

Understanding what causesobesity is key to knowinghow to prevent it in the

first place. The good news is thatobesity is both preventable andtreatable. It is much easier, however, to prevent than it is totreat. If you aren’t overweight orobese, now is the time to find outhow to stay that way. If you arealready overweight or obese andyou want to make changes toyour lifestyle, there is no miraclecure, no magic pill that willchange your weight or body type.But making changes to your dietand exercise and eating habitswill allow you to safely and grad-ually lose weight.

ExerciseThe first step to preventing obesity, or to losing weight, is exercise.

As we discussed in Part 2, yourbody works best when the num-ber of calories you eat and thenumber of calories you use up arenearly the same. The best way touse up lots of calories all at onceis to exercise.

Your body will just use up activecalories in the first 20 minutes of working out. To use up storedfuel (or fat), you need to work out for more than 20 minutes.For this reason, it is better toexercise in larger chunks of time. If, however, you don’t have largechunks of time available, exercis-ing in ten-minute bursts is betterthan nothing at all.

In order to stay at your currentweight, you should do at least 30 minutes of moderate-intensityphysical activity, like swimmingor brisk walking, every day.During moderate-intensity activi-ties, you should be able to talkwithout a problem. This level ofactivity will use up the caloriesin a healthy diet.

The calories youfeed your bodyshould not bemore than thecalories yourbody uses upduring physicalactivity andwith other bodily func-tions, likebreathing.

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If you want to prevent gradualweight gain or if you need to lose alittle bit of weight, you should doan hour of moderate- to vigorous-intensity activity every day. Thislevel of activity leaves you out ofbreath at the end.

If you want to lose weight, youshould increase your physicalactivity to 90 minutes at a moderate-intensity level.

To be physically fit, you shouldinclude three types of physical activity in your workout:

• Cardiovascular conditioning(or aerobic exercise) is active and improves your heart health.It also burns the most calories.This category includes running,biking, and swimming.

• Stretching improves your body’sflexibility. This includes tai chiand yoga.

• Resistance training improvesmuscle strength and endurance.This includes activities likeweight lifting.

If you have not exercised in a longtime, expect to be tired and sore at first. Within a week, your bodywill have adjusted. If you experi-ence chest pains at all, stop imme-diately and call your doctor. And if you have a health condition,double-check with your doctorbefore you start or change yourexercise program.

A man, who would manage to lose100 pounds in the following year,participates in a weight control program for individuals with seriousweight and health problems.

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Part 4: How Can Obesity Be Prevented and Treated?

Good nutritionThe government has changed itsrecommendations about food overthe years as we learn more aboutthe science of nutrition.

An average diet should include2,000 calories a day. Based onyour weight, your weight goals,and your physical activity level,you may need fewer or more calo-ries. Do not forget to include anydrinks (other than water) thatyou have when you’re figuringout your daily calories.

In fact, water is a good placeto start when planning ahealthy diet. While there is

no one number that fits every-one scientists suggest peopleaim for 48–64 ounces of water

How Hard Should I Be Exercising?

To figure out your maximum Let’s say you’re 30 years old. My age is ________.heart rate, subtract your To find your maximum heart My maximum heartage in years from 220. rate: 220-30=190 rate (MHR) should

be 220-(my age)= _______

To find your target heart To find your target heart rate: My target heart rate rate (60–85% of how hard 190x.6=114 would be:your heart can beat), 190x.85=161.5 _____ (My MHR)x.6= ____multiply that number by .6 _____ (My MHR)x.85= ____(for 60%) or .85 (for 85%).

You want your heartbeats Your heart should be When I’m exercising at myper minute to fall between beating between 114 and hardest, my heart shouldthose numbers. 162 beats per minute when beat between ____ and

you’re exercising at your ____ times per minute.hardest.

Check your pulse (heartbeats per minute) by putting two fingers on the side of your neckand counting the beats for 1 minute. Use a watch that keeps track of seconds to time your-self. (If you find it’s hard to keep track of your heart rate for a whole minute, you can checkit for 30 seconds and double that number.)

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a day. (Some scientists suggestthat you can find the rightamount by dividing your weightin pounds in half and drinkingthat many ounces.) You can con-sume water in other ways (somefruits and vegetables, fruit juice,coffee, soda, and milk are highin water content), but many ofthose other drinks are high incalories, caffeine, or sugar. Inaddition to cutting calories, bydrinking more water you canhelp decrease your appetite. Thebody's signals that it is hungryor thirsty are very similar, anddrinking a glass of water as afirst response can be a goodstep toward limiting the amountof food you eat.

You should eat a wide variety offoods rich in vitamins, minerals,proteins, healthy unsaturated fats,

Low-cost exercise ideas• Use ordinary household goods instead of dumbbells for

weight training. You can fill empty milk, water, or dishwash-ing-detergent bottles with water or sand and use duct tapeto make sure the tops stay on. You can adjust how much isin the container to get different weights. Canned goods canbe used as hand weights or a pair can be put into tube socksto use as ankle or wrist weights. Bags of cereal, potatoes,and frozen vegetables come in sizes up to 10 pounds.

• Walk more. Park further from the office or store if youdrive. Get off the bus or the subway a stop earlier thanusual if you take mass transportation. Take the stairs or walkup the escalator—a few extra times if you can. Many mallsopen early to let people walk laps in a safe, dry location.

• Use the library. Most libraries have free video sections thatinclude workout tapes or DVDs.

• Take advantage of public facilities. Many cities have publicparks, public pools, and park and recreation centers thatpeople who live in town can use for free or very littlemoney.

• Use your baby as a weight. Walking with your baby in ababy-backpack uses more calories than pushing him or herin a stroller.

• If you have children, ask your schools to have gym classes orrecess every day or to form after-school exercise clubs. Thiscan help prevent childhood obesity and lower your child’sweight.

• Put on up-tempo music. You can dance to it in your apart-ment without anyone seeing you. Or you can do yourhousecleaning to it. You’ll clean much faster—which is goodfor your body and gets your cleaning over with!

• Jog in place, jump rope, or do a combination of push-upsand sit-ups while you watch TV.

• See if anyone at your place of work or worship wants tostart an exercise class or a walking club.

• If you have a video game system, some games encourageplayers to use their whole body while playing.

• Thrift stores may have used exercise equipment they’re sell-ing for a low cost.

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Part 4: How Can Obesity Be Prevented and Treated?

and fiber. These are contained infoods like vegetables, fruits, nuts,fish, beans, and whole grains.

Americans often don’t eat enoughfruits and vegetables. You shouldconsume two cups of fruit and twoand a half cups of vegetables aday. It is important to eat differ-ent kinds (green leafy, orange,legumes, starchy, and other veg-etables) every day because differ-ent kinds contain different levelsof vitamins.

Whole grains are another impor-tant part of a diet. Try replacingother carbohydrates with wholegrain breads and pasta or wildrice.

Americans consume more thanthe recommended amounts of sat-urated and trans fats, cholesterol,sugar, and salt. You should limitfoods in your diet that containthese items and replace themwith unsaturated fats. Your totalfat intake should be 20–35% ofyour total calories. Less than 10%of your daily calories should comefrom saturated fats. Dietary cho-lesterol should be limited to lessthan 300 mg/day.

In 2005, the Food and DrugAdministration came out with anew food pyramid. What this newpyramid looks like depends onyour age, gender, and physicalactivity.

Each one will look slightly differ-ent, but they all resemble the foodpyramid on this page.

It can be difficult to understandjust from looking at the picturewhat everything means, but thecolors stand for different types offood and their width stands forhow much of your diet each oneshould be.

ORANGE: Grains. You should eatat least three ounces of wholegrains a day.

GREEN: Vegetables. You shouldeat at least five servings of veg-etables a day, totaling two and ahalf cups for an average adult.They should include dark green,starchy, orange, dry beans andpeas, and other vegetables.

RED: Fruits. You should eat threeservings, or two cups, of fruit aday.

MyPyramid.govSTEPS TO A HEALTHIER YOU

(You can visit theMyPyramid.govWeb site to findout what your personal foodpyramid shouldlook like.)

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Controlling portion sizesSo you know your BMI and how many servings you need of each food, but you don’t wantto weigh your food or carry a measuring cup around with you to find out the rightamount. What’s the answer?

ESTIMATE:

• One quarter of a cup (a serving of dried fruit) is the size of a golf ball.

• One half of a cup (a serving of vegetable juice) is the size of a standard yo-yo or an icecream scoop.

• One cup (a serving of leafy green vegetables) is the size of a tennis ball or a baseball.

• One ounce (a serving of cheese or beans) is the size of two dice.

• Three ounces (three servings of cooked meat or fish) is the size of a deck of playing cards.

• Two tablespoons (a serving of salad dressing) is roughly half the size of the ladle.

As you can see, if you’ve been filling your plate with food, you’ve probably been eatingway too much!

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Part 4: How Can Obesity Be Prevented and Treated?

YELLOW: Oils. You should limityour oils to six teaspoons a day ofunsaturated oils.

BLUE: Dairy products. You shouldconsume no more than three cupsof low-fat dairy products a day.

PURPLE: Low-fat Meats andBeans. You should eat five ouncesa day.

The stairs on the side of thepyramid remind you to includephysical activity every day inyour plan to live a healthier life.

Treatment methodsIf you are already obese, eatinghealthier and exercising is a goodway to start to lose some weight.If you have tried those methodsbefore and haven’t had much

Healthy ethnic cuisine

When you start to think about changingyour diet, you don’t want to lose out onthe foods of your childhood. Here aresome healthier ethnic cuisine adaptations:

SOUL FOOD:• Flavor collard greens and beans with

smoked turkey instead of pork fat• Season carrots with honey and cilantro

instead of butter and salt• Use frozen instead of canned collard,

turnip, and mustard greens (all of whichare excellent for you)

• Substitute spice seasonings for salt• Substitute two egg whites for a whole

egg in desserts• Bake sweet potato chips instead of

frying sweet potato fries• Cook in olive oil instead of butter, lard,

or bacon grease• Choose skinless poultry (or remove the

skin before eating) and lean cuts ofmeat (such as round, sirloin, and loin)

• Use low-fat or fat-free milk in macaroniand cheese

ASIAN FOOD:• Steamed instead of fried rice• Steamed, poached, roasted, boiled or

barbecued meats instead of battered or fried

• Dishes without MSG

• Stir-fry with less oil• Use more vegetables and less meat

LATINO FOOD:• Rice and black beans• Soft corn tortillas instead of fried corn

tacos or flour tortillas• Salsa or pico de gallo instead of cream

sauce or sour cream• Spicy chicken• Baked, grilled, or pan-seared options• Seafood or beans instead of meat• Fajitas instead of quesadillas• Use low-fat or fat-free cheese• Grill plantains instead of frying them• Drain the fat from meat before serving

NATIVE AMERICAN FOOD:• Consume fewer drinks containing sugar

or alcohol• Have only one piece of fry bread at

special occasions• Substitute bannock (oven) bread

for fry bread• Eat more lean meats, such as buffalo

EUROPEAN FOOD:• Red sauces instead of cream or

butter sauces• Piccata• Primavera (non-cream sauces)• Sautéed or grilled meats instead of fried• Sun-dried or crushed tomatoes• Minestrone soup

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luck, your doctor may talk to youabout other ways to lose weight.

DietsEveryone knows someone who hastried one diet plan or another: TheSubway sandwich diet. The cerealdiet. The cabbage soup diet.Weight Watchers. Jenny Craig.Atkins. South Beach. There arenearly as many diet plans as thereare people!

Usually a diet plan works at first.The person takes off some weight.

But then they come off the dietand the weight comes right back.

A successful diet combines severalthings:

1. Eating fewer calories. Somediets do this by replacing yournormal food with their own, pre-measured food to make sure youpay attention to portion size.Others suggest ways you cansubstitute lower-calorie foods foryour normal ones. Remember, ifyou take in too many calories—no matter how healthy theirfood source is—your body willconvert the ones you don’t useup into fat.

2. Balanced meals. Most healthydiets will have you eat less ofthe foods that Americans tend toovereat, such as trans and satu-rated fats and sugary carbohy-drates. They also emphasizeportion control, leading you toeat more of the healthy, low-calorie foods and less unhealthy,fattening foods.

3. Long-term goals vs. short-termgoals. Almost every diet planwill help you to lose weightright at the beginning of it sim-ply because you are changingwhat and how you eat. A gooddiet will give you tools for mak-ing these changes part of yourlifestyle in order to keep theweight from coming back. Yo-yo

Don’t starve yourself!

You might think that the fastest way to lose weight would beto stop eating. After all, if you keep up your normal level ofactivity and keep using the same amount of energy, then youshould use up lots and lots of stored energy in fat cells, right?

Wrong! As we mentioned earlier, our bodies are outdated inhow they process food. When new energy stops coming intothe body, the body is programmed to think there’s a problemand that there isn’t enough food. It becomes more efficient andtries to use less energy for activities. It also looks for otherplaces from where it can draw energy.

The body starts by using lean tissue and muscle to provide itwith the calories it needs to keep working. This can lead tomuscle loss. Since the amount of muscle determines how muchenergy our body needs, having less muscle means we use lessenergy. Our metabolism slows down—by up to 45% over time—when the body loses a lot of muscle while taking in too fewcalories.

If we were in an area suffering from a hard winter or were fac-ing a famine, this would be a good strategy because it keeps usalive longer. But if we’re trying to lose weight, it’s a very badidea. It’s much more effective—and healthier—to use a differ-ent method of losing weight, such as eating healthier, exercis-ing, or talking with a health care provider about diet drugs orweight-loss surgery.

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diets where you lose weightand gain weight quickly over ashort period of time areunhealthy. It is much healthierto lose a half to two pounds aweek over a longer period oftime.

4. Diets that specifically ban cer-tain types of food do not tend tobe successful in the long run;you might be able to keep fromeating something for a shortperiod of time, but it’s hard tonever eat your favorite foodsagain.

5. Focus and support. It is easierto lose weight if you are payingattention to what, when, andwhy you are eating. Some peo-ple overeat without noticing.The act of focusing on your foodcan help to curb that tendency.Many successful diets also com-bine some form of professionalcounseling or group support.Knowing that you are not alonein wanting to lose weight andin slipping into unhealthybehaviors every once in a whilecan help you to reduce yourstress levels and to make long-term changes to your lifestylethat will help you lose extraweight and to keep it off.

6. Exercise. All diets will tell youthat it is necessary to exercisein order to burn stored fat.

Diet drugsYou’ve seen the ads on TV and theInternet and in magazines. “Loseweight while you sleep!” and“Shed pounds without exercise!”sound very promising. It would begreat if you could just take a pilland have your excess fat meltaway without any extra work onyour part—and people spend lotsof money hoping these commer-cials and infomercials are givingthem a miracle cure.

The truth is that there is no mira-cle cure. Drugs that you can buyover the counter or that you sendaway for on TV are not theanswer. Dietary aids, supple-ments, and herbal medicines donot have to be tested by the feder-al government to make sure theyare safe for you or that they dowhat they promise. Some scien-tists hope to find new informa-tion about herbs and dietary

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supplements. The NationalCenter for Complementary andAlternative Medicine warns thatno single supplement has beenproven effective in large-scalestudies. They do go on to saythat there are some smallerstudies of certain supplementsthat suggest that further testingis necessary.

For now, though, these drugs areineffective; they don’t do anythingextra like they promise they will.Usually, they have very fine printthat says you must stick to a low-calorie diet and exercise regularlyin addition to taking their pill orpowder to see any real weightloss—and you can lose weight bydoing both those things and nottaking their drugs!

Some “miracle drugs” are evenworse and are actually dangerousto your health. Some are addictive.Others cause serious health prob-lems. Ephedra, for instance, hasbeen linked to seizures, heartattacks, heart beat irregularities,and high blood pressure. It is notlegal to sell it in the U.S. as a pill,but it is still sold as an ingredientin some “health” teas, as well asover the Internet, where peoplecan ship it from places where itcan be sold legally.

Remember, the people who adver-tise diet drugs on TV and theInternet are in the business of

making money. If you are curiousabout any of the products you seeor read about, talk to your healthcare provider. He or she can helpyou figure out if it’s worthwhile foryou to try. And the main thing tokeep in mind is that if it soundstoo good to be true, it almostalways isn’t going to help you.

However, if you are obese, youhave obesity-related health prob-lems, and traditional diets andlifestyle changes have not workedfor you, there are some drugs thatyour health care provider can pre-scribe. Prescription diet drugs can,when taken properly, carefully,and under a doctor’s supervision,help you begin to lose weight.These prescription drugs are verypowerful, though, and you shouldseriously think about their sideeffects when making your decision:

Sibutramine (sold as Meridia)changes the way your brain worksto make you feel fuller sooner. Itsbad side effects include high bloodpressure, constipation, and notbeing able to sleep. No one withhigh blood pressure or heart dis-ease, or the risk of heart disease,should take it.

Orlistat (sold as Xenical) keepsyour intestines from breakingdown and absorbing fat. Because italso keeps your intestines fromabsorbing vitamins A, D, and E,you will also need to take a daily

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supplement. Its side effectsinclude frequent oily bowel move-ments, diarrhea, and pain in yourmidsection. There have been alle-gations that orlistat is linked tocertain types of cancers.

Phentermine (sold as Adipex-P,Pro-Fast, and Ionamin) keeps youfrom feeling hungry. You shoulduse it for less than three monthsonly, and the weight you lose cancome back after you stop takingit. Its side effects are nausea anddizziness.

Other short-term appetite-sup-pressants include diethylpropi-on and phendimetrazine.In 2002, less than 2.4% of thosepeople who were medically eligi-ble for diet drugs asked for them.

Weight-loss surgeryBetween 1998 and 2002, the num-ber of people who had weight-losssurgery quadrupled.

There are several different types of weight-loss surgery:

• Gastric bypass (Roux-en-Ygastric bypass) surgeryinvolves re-routing your stom-ach. A surgeon will stapleclosed a tiny pouch the size ofan egg (which can hold anounce or so of food) and attachthe middle portion of the smallintestine directly to it. Thiscloses off most of the stomach,as well as the first section ofthe small intestine. The bene-fits of this surgery are that thepart of the stomach that is nolonger being used still secreteshealthy digestive juices and

Part 4: How Can Obesity Be Prevented and Treated?

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The Roux-en-Y gastricbypass procedure involvescreating a stomach pouchout of a small portion of the stomach and attachingit directly to the small intestine, bypassing alarge part of the stomachand duodenum. Not onlyis the stomach pouch too small to hold largeamounts of food, but byskipping the duodenum, fat absorption is substantially reduced.

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your small intestine doesn’tabsorb as many calories.Research indicates that patientscan expect to lose between 48and 74% of their excess bodyweight after the first year alone,followed by gradual and slowerrates of weight loss until theperson’s body weight becomesbalanced.

Gastric bypass, which is themost common weight-loss sur-gery, can be done as a laparo-scopic surgery. That kind ofoperation uses a small instru-ment with a tiny cameraattached to it that’s insertedinto your body through smallcuts, instead of having to makelarge cuts, so a surgeon can fithis or her hands into your body.Laparoscopic surgery has ashorter healing and recoverytime.

• Adjustable gastric bandinguses a band made of hollow rub-ber to reduce the size of theopening to the stomach, helpingyou to feel full much sooner. Theband can be tightened or loos-ened or removed altogether.

• Vertical gastric banding usesboth a band and staples toreduce the size of the opening tothe stomach. Once the mostcommon weight-loss surgery,this is not used often anymore.

• Biliopancreatic diversion is amuch more complicated surgeryin which the doctor removesmost of the stomach and bypass-es both the first and the middlesections of the small intestine.This type of surgery can lead tonutritional deficiencies, so it isnot performed as often as someof the others.

Weight-loss surgery has beenshown to be very effective in help-ing severely obese people loseweight. It is important to keep inmind, though, that weight-losssurgeries are risky, as are all sur-geries. Possible side effects includegallstones, dehydration, hernias,ulcers, and vitamin and mineraldeficiencies as well as the threat of death, blood clots, pneumonia,and leaks at the points of surgery.And while weight-loss surgery issuccessful for many people in helping them to lose extra pounds,some people do regain the weightthey lose after the surgery. It isimportant to talk with your doctorabout your options and to seriouslyconsider this decision.

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Part 4: How Can Obesity Be Prevented and Treated?

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A Walking Testament to the Power of Exercise

“Shop ‘til you drop” is a battle cry for many mall patrons, butfor Pat Langer and other dedicated mall walkers, the onlything dropping is pounds, inches, and a sedentary lifestyle.

More than a decade ago the famous Mall of America inBloomington, Minnesota, opened its doors to customers andwalkers alike. Langer was one of the original “Mall Stars,” asthe walking participants are known. Over the past ten years—thanks in large part to a two-hour-, nine-mile-a-day, five-days-a-week walking regimen—she has lowered her cholesteroland shed more than 60 pounds while gaining flexibility.

“I began walking as part of exercise 15 years ago because ofthe onset of osteoarthritis,” says Langer, a Minnesotan native.“I knew that I had to take exercise seriously, even though I

thought I had always been pretty health conscious.”

Mall walking has enabled Langer to stick to her exercise regardless of snow accumula-tion or below-zero temperatures, the hallmarks of a true Minnesota winter. Aside fromoffering a pleasant temperature, the mall provides a smooth, controlled path, free ofbumps, potholes, and rain puddles, not to mention speeding cars and chasing dogs.

The decision to walk come rain or shine has paid huge dividends for Langer, especiallywhen she underwent knee replacement surgery. Just one week after her operation, she was on a stationary bike—a step in recovery that normally takes six weeks. Doctorsattribute her remarkable recovery to a good range of motion and flexibility—therewards of walking.

“I would recommend mall walking to anyone. There is such an enormous benefit to yourhealth and well-being, and it’s a type of exercise that virtually anyone can do,” saysLanger. “You can set your own pace. Many people walk with the help of a cane or awalker, while others are speed demons. Likewise, you can walk with a friend or walk byyourself—whatever you prefer.”

For her part, Langer, a piano teacher and mother of three grown children, enjoys walk-ing early in the morning, but varies her routine depending on her work schedule. Shejust puts on her walking shoes and comfortable clothes, jumps in her car, and withinseven minutes she’s able to start walking. She doesn’t worry about packing a headsetbecause she “loves to hear the rhythm of life.”

More than 3,000 individuals participate in the walking program at the Mall of America,where a lap around one level of the mall equals just over a half-mile. Given the highlevel of participation, it isn’t unusual for Langer to recognize plenty of familiar faces. “I walk nine miles a day, so I tend to see a lot of fellow walkers,” she says.

So does Langer go to the mall to shop? As they say in Minnesota, “You betcha!” Afterall, she wears out about four pairs of walking shoes each year!

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Part 5: What Does ResearchTell Us About Obesity?

Current lines of research

As science, technology, andmedicine have advancedover the centuries, so has

humankind’s understandingabout the benefits of propernutrition and fitness and thekinds of diseases and disabilitiesthat come from obesity.

Over the years, many thousandsof researchers in all fields of sci-ence have dedicated their livesto investigating and discoveringexactly how obesity leads to orworsens serious diseases andconditions like diabetes, highblood pressure, and heart dis-ease. They also are looking atthe health benefits of good nutri-tion and fitness.

Today, many of these health dis-coveries are well publicized, aspeople read about them in news-papers or online or hear aboutthem on the news. While muchhas been learned about thestrong relationship between eat-ing well, exercising, and goodhealth, many questions remainunanswered. Ongoing and pastclinical trials have helped

scientists learn about diseases—and have helped save the lives of many people through thatknowledge. Past, present, andfuture findings in all areas ofresearch will only improveAmericans’ chance of living long,healthy lives without chronic ill-nesses.

Population studies. Research-ers can learn a lot about the pos-itive and negative effects of goodand bad nutrition and fitness bystudying groups of people over along period of time.

Scientists arelooking into all areas ofnutrition, fromwhat food ishealthiest tohow our genesaffect our riskof obesity.

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One very important study hasinvolved studying the high rates of diabetes and obesity among thePima Indians of Arizona. Amongother things, this ongoing 30-yearstudy has let researchers establishevidence that regular exercise anda healthy diet can delay the devel-opment of diabetes.

These findings, along with otherstudies, have helped the medicalcommunity conclude that beingoverweight or obese is a significantrisk factor of diabetes.

The Pima Indian researchers havebeen able to further explore therelationship between nutrition, fit-ness, and diabetes by comparingtheir findings with another verysimilar tribe of Pimas in Mexico.Compared with the Arizona Pimatribe, the Mexican tribe has ahealthier lifestyle that includeseating more nutritious foods and

living more active lives. The Pimatribe of Mexico has a much lowerrate of diabetes than the Pimatribe of Arizona, which also sup-ports their findings about thestrong relationship between nutri-tion, fitness, and diabetes.

Genetic research. Geneticresearch plays a large part in whatscientists and researchers arelooking at in terms of obesity.Scientists recently found the firstcommon gene that increases therisk for obesity. The gene, whichseems to affect how the body storesand burns fat, appears to be pres-ent in 10% of the population andboosts the risk for obesity in thisgroup by 30–50%. Scientists hopeto identify the gene itself and tolearn more about it to help thembetter understand obesity and howto treat it with drug therapy.Scientists have already identifiedother more rare genes that seem to affect obesity.

Obesity has been linked to manyhealth conditions, and eating ahealthy diet and exercising havebeen shown to play a major role inthe fight against illness. We willknow more and more about theroles of diet and exercise whenmedical science is able to identifywhich people are genetically predisposed to develop specific diseases.

The mouse at leftis missing the genethought to beinvolved with obe-sity and is thin.The mouse on theright had no generemoved and isobese. Scientistswill use these miceto test obesitytreatments anddiabetes drugs.

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Part 5: What Does Research Tell Us About Obesity?

Currently, a good part of geneticresearch takes place in a labora-tory, where researchers studygenes using technologicallyadvanced equipment to look athow the genes cause disease inthe body (and ways to prevent itfrom happening). Genetic studiesalso take place among people,where researchers interview par-ticipants and their families tofigure out which diseases or dis-orders were passed down, whichmembers developed the condi-tion, and how the illness ran itscourse.

Current studies on the effects ofnutrition and exercise on inherit-ed diseases will add to discover-ies being made at the cellularlevel. Among the many fitness-based studies is one that found

that obese men who exercisedevery day for three weeks andate a high-fiber, low-fat diet low-ered their cholesterol and bloodpressure levels and eased heartstress and other indicators ofheart disease despite only losinga little bit of weight.

Weight management. Anotherimportant part of the medicalresearch effort is to search forbetter, healthier, and more effec-tive ways for people to loseweight and keep it off. In thevarious studies dealing withweight loss, there is added sig-nificance simply because of theimportance obesity has withregard to so many other healthproblems.

One such study has taken placeat the University of Pennsyl-

Without volunteers of all ages,scientistswould notbe able totest newtreatmentsand to comeup with newways to preventweight gainor to loseweight.

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vania Medical Center’s Weight andEating Disorders Program. Theyreceived funding to develop betterlong-term ways to help obese menand women manage their weight.Another similar study is trying to

develop ways of helping youngchildren who are obese and whoare at risk for developing heartdisease and diabetes.

Another major research effort fromthe last ten years seeking to helphigh blood pressure patients loseweight and lower their sodiumintake is the Dietary Approachesto Stop Hypertension (DASH)study. Supported by the NationalHeart, Lung, and Blood Institute,the DASH diet is a healthy low-sodium, low-cholesterol eatingplan that emphasizes eating lots offruits and vegetables and consum-ing low-fat dairy products. Withinweeks, it was shown to significant-ly lower blood pressure levels andweight of men and women of allages, races, physical conditions,and medical backgrounds. Studieshave shown since then that theDASH diet also lowers “bad” cho-lesterol (LDL-cholesterol) andhomocysteine (an amino acid),which has been associated with a greater risk for heart disease.

Minority participants in the DASHstudy, particularly AfricanAmericans, benefited even morethan white participants from the diet. In addition to samplemenus and recipes, the DASH dietplan also provides a form to docu-ment eating habits before startingthe diet and a chart that will helpmanage and guide a person’s shop-ping and meal planning once a

Obesity and Your Brain

What role does the brain play in obesity? Is it just amatter of calories in must equal calories out? Or is theresomething more complicated at work?

Some scientists, who specialize in the way the brainworks, are looking at a number of ways in which thebrain may affect obesity. They believe the brain may playa key role both in who becomes overweight and how thebody reacts to attempts at weight loss.

For instance, a number of scientists are looking at theway the brain responds to two chemicals in the body.One, leptin, is produced in fat tissue and sends messagesto the brain about the amount of nutrition the bodyneeds. When working properly, leptin levels increase ordecrease at the same time body fat levels do and tellthe brain whether it should be hungry or full. The brainsof some obese people, however, do not seem to respondto leptin, meaning that their appetites don't shrink justbecause their bodies have enough fat. Those looking atthe role leptin plays include NASA scientists, who havetested rats at different levels of gravity to find out howand why leptin works, why it sometimes doesn't work,and how the body’s response to leptin could be fixed.

The other chemical, ghrelin, is found mostly in the stom-ach and helps to regulate the body's energy. Ghrelinslows metabolism and tells your brain when there is nofood in the digestive system so that it should feel hun-gry. Scientists are looking into several aspects of ghrelin.One study suggests that ghrelin isn't as affected by fatas by protein or sugar calories, meaning that a high-fatdiet doesn't actually lessen the signal to your brain thatyou're hungry. Others are looking at why ghrelin doesn'tseem to work right in obese people. Yet others are test-ing a vaccine that prevents ghrelin from reaching thecentral nervous system and delivering its message to thebrain.

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person starts. By testing theDASH diet and other nutrition-based efforts, researchers work tofind better ways for people withor at risk for hypertension to eathealthy and manage their eatinghabits more effectively.

Researchers also are looking moreclosely at other treatment plans.They are trying to find new drugsand improve older ones to takebetter advantage of what we havelearned about obesity. They aretrying to figure out if drugs thatare now prescribed for non-weight-related reasons, such asdiabetes or depression, have addi-tional properties that make themgood to use as diet drugs. Doctorsmay hear of some drugs thatseem to help patients lose weightin addition to or instead of treat-ing their initial health problem.Then, doctors want to find out ifthese drugs can help everyone orjust some people.

Other studies look at the safety ofdiet drugs. The Sibutramine inCardiovascular Outcomes Studyis in the midst of looking at whatrole sibutramine plays withregard to cardiovascular disease.Some people are trying to figureout if it’s still safe to prescribe.Others are looking at whether itjust needs to be taken with otherdrugs to make it safer for those at risk for cardiovascular

disease. In the past, some drugswere discovered to create moreproblems than they solved. FenPhen and Redux, for instance,were removed from the marketwhen they were found to causeheart valve problems in some people.

Still other studies have foundthat just using diet drug therapyalone is not effective. Those wholost weight without changingtheir lifestyle regained the weightafter they stopped using the drug.

Other scientists are focusing theirresearch on weight-loss surgery.Some are looking at the role ofpre-existing health conditions onthe success of surgery. One studyshowed that if patients sufferfrom depression, they have apoorer health-related quality oflife after their weight-loss surgerythan those who do not suffer fromdepression. This can help doctorsbetter screen patients before sur-gery and treat them after they’vehad the surgical procedure.

Many researchers have found evi-dence to support the effectivenessof weight-loss surgery. A numberof studies show that weight-losssurgery is more effective thanmaking lifestyle changes com-bined with drug therapy in reduc-ing weight over the long run.

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Another, the Swedish ObeseSubjects study, looked at the long-term weight loss of 500 patients. Itfound that those who had hadweight-loss surgery kept off 16% oftheir body weight over the courseof eight years. The LongitudinalAssessment of Bariatric Surgery islooking at the risks and benefits ofdifferent types of obesity surgery

and their impact, as well as help-ing to identify those who will bene-fit most from them.

The important role of volunteersResearchers and medical science ingeneral would not be able tounderstand obesity—or make

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Is a little baby fat dangerous?

At one time, people generally believed that chubby cheeks and a little "babyfat" showed that infants were getting enough of the right nutrients. But withtoday's focus on when the obesity problem begins, scientists are starting toask if the conventional wisdom is correct.

One doctor at Children's Hospital of Philadelphia believes that the problem ofobesity starts as early as the first few months of life. He has been combingthrough records of thousands of babies born in the early 1960s and has foundthat the amount of weight that children gain in the first four months of lifeis linked to childhood obesity at age 7, regardless of birth weight or if theywere overweight at a year old.

Among his other studies this same doctor has found that a large weight gainduring the first week of life among babies being fed formula seems to tie inwith being obese decades later. For every extra 3.5 ounces a baby gains inweight in its first eight days, his or her chances of being overweight as anadult also increase by 10%. These studies seem to show that early infancy isan important time period for the development of obesity and metabolism.

Other studies show similar results. One found that large babies and those whogained weight quickly over the first two years of life were nine times morelikely to suffer from obesity later on. Another showed that low-birth-weightbabies who gained the most weight during infancy and early childhood weremost likely to suffer from high blood pressure as adults.

Yet more studies look at how and how much infants are fed. Infant rats thatare regularly overfed have an increased level of a hormone known as leptin,which helps to regulate appetite. Breastfeeding is another area of scientificexploration. Scientists have found the longer an infant is fed only breast milk,the lower his or her risk of childhood obesity.

In short, scientists are still trying to find out when exactly obesity becomes aproblem for growing children. While there is cause for concern if your babygains weight quickly, scientists say not to overreact—particularly if your baby isbreastfed only—and to talk to your baby's doctor if you think there could bea problem.

inroads against the diseases itcan lead to—without the help ofthousands of volunteers in thelast century alone. As participantsin research studies, volunteersare willing to share their personalmedical histories; participate inclinical studies, often for long

periods of time; and accept manyother sacrifices in order to helphumankind’s ongoing effort tolearn more about the health bene-fits of good nutrition and fitness.When conducting a study, it iscritical for researchers to be ableto access and study hundreds, if

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not thousands, of people of allages, races, and lifestyles in orderto determine how certain diseases,activities, and foods affect differentpeople. This enables them to gath-er more accurate race-, age-, orgender-specific information andpossibly to uncover new insights orways of treating special groupswith specific conditions.

When different subgroups or com-munities participate in a researchstudy, they are able to take advan-tage of the most current and per-haps most effective medical treat-ment for any given disease or con-dition. The quality of care volun-teer patients receive during thecourse of a study is often very highand very beneficial. Volunteersalso benefit from knowing thattheir participation may one dayhelp others.

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Eating well and staying fitcould save your life oneday. Millions of Americans

are going to face a variety of life-threatening diseases because theyare overweight or obese. A goodway to commit to healthier livingis to stay informed about healthimprovements and to make thempart of your life. Another way isto help others learn more aboutgood health:

Educate yourself. Reading thisbook is a great start. It is impor-tant to continue to educate your-self about obesity, particularly asyour get older and as new infor-mation and research from themedical community comes out.Good sources of information arethe library and the Internet. Aska librarian for help in yoursearch, if necessary. Make sure toshare the interesting thingsyou’ve learned here and will learnin the future with your family,friends, and community.

Eat healthy. Think about yourcurrent diet. How does it comparewith what you’ve learned abouthealthy foods? What are some of

the unhealthy foods you regularlyeat that can be replaced byhealthier ones? Keep thinkingabout your diet and make simplechanges to make you healthier inthe long run. Does obesity or anobesity-related condition run inyour family? Use the library orone of the Web sites in theResources section of this book(starting on page 61) to find outwhat kinds of foods, activities, or tests you can use to preventobesity. Commit now to bettereating, and think long term. Talkwith your friends and family, too,about the serious benefits of eating better.

Conclusion

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Stay fit. How much do you exer-cise? What physical activities doyou enjoy most? Do you spend atleast an hour a day most daysbeing active? If not, it is never toolate to start—and the benefits arealmost immediate! As with improv-ing your diet, half the trick ofbecoming a person who works outregularly is the slow and gradualcommitment you make to exercis-ing as a way of life. Exercising canmake you feel and function betterboth inside and out. Among otherthings, it also fights off diseaseand depression. Share the informa-tion you have learned about fitnesswith the people you know.Everyone likes to learn somethingthat might be lifesaving.

Monitor your health. In additionto watching your diet and gettingenough exercise, it is important tomeet with your health careproviders on a regular basis. Yourhealth care providers can help youkeep track of your BMI, test youfor conditions for which you are atrisk, and help you make goals forlosing weight or improving yourdiet. Finding out if you have anobesity-related condition can bescary, but it is better to find out forsure. Then you can learn how tomanage your symptoms and pre-vent your condition from gettingworse.

Get involved in your communi-ty, at schools, or in researchtrials. Find out about the variousobesity prevention and treatmentprograms that take place in yourcommunity and get involved in oneyou are interested in. Do theschools in your community servehealthy meals, and do they havegym class every day? Let theschool system know how importantthis issue is to you. How are thefitness opportunities for bothadults and children in your com-munity? You can have fun andmeet others by participating inthese activities or by helping toexpand them for the betterment ofothers. There may also be healthresearch trials that are takingplace near you. You can become avolunteer or help someone youknow get involved or participate.

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Appendix 1: Questions to AskYour Doctor About ObesityWhat is my body mass index?

Do I need to lose weight?

Am I at risk for any health conditions?

Should I be tested for any conditions?

Do I need to make changes in my lifestyle to prevent any illnesses?

What help is available for making those changes?

Can I take part in any exercise or sport I want to?

What is a healthy eating plan for me?

Should I look into weight-reduction surgery or weight-loss drugs?

What can be my short-term goals for control of my obesity?

What can be my long-term goals?

What is the treatment plan?

What lifestyle changes are required by this treatment plan?

Do I need to see any specialists?

What medications will help control the complications of obesity?

What is the schedule for check-ups?

Can you help me locate a clinical trial to join?

How can I help my child lose weight if he or she is obese?

How can I help my child maintain a healthy weight?

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Appendix 2: Taking Part inResearch Studies—Questionsto AskA research study is a way of finding answers to difficult scientific orhealth questions. Here are some important questions you should ask ofanyone who wants you or members of your family or community to bepart of a research study:

1. What is the study about?Why are you doing the study?Why do you want to study me or people like me? Who else is beingstudied?What do you want to get out of the study?What will you do with the results?Have you or others done this type of study ever before? Around here?What did you learn?

2. Who put the study together?Who is running or is in charge of the study?Whose idea was the study?How were people like me part of putting it together?Who are the researchers? Are they doctors or scientists? Who do theywork for?Have they done studies like this before?Is the government part of the study? Who else is a part of the study?Who is paying for the study?Who will make money from the results of the study?

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3. How can people like me share their ideas as you do the study?How will the study be explained in my community?Who among people like me will look at the study before it starts?Who among people like me are you talking to as you do the study?A Community Advisory Board?Who from the study can I go to with ideas, questions, or com-plaints?How will people like me find out about how the study is going?

4. Who is going to be in the study?What kinds of people are you looking for? Why?Are you trying to get minorities into the study?Are you including people younger than 18 years old?How are you finding people for the study?Is transportation or day care provided for people who take part inthe study?Do I need to sign anything in order to participate?Will you answer all of my questions before I sign the consent form?Can I quit the study after signing the consent form? If I quit thestudy, will anything happen to me?

5. What will I get out of the study?What are the benefits?Is payment involved? How will I be paid?Will I get free health care or other services if I participate? For howlong?Will I get general health care or psychological care if I participate?For how long?

6. How will I be protected from harm?Do I stand a chance of being harmed in the study? In the future?Does the study protect me from all types of harm attributable to it?If I get harmed, who will take care of me? Who is responsible?If I get harmed in any way, will I get all needed treatment? Whopays for treatment?

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7. How will my privacy be protected?Who is going to see the information I give?Will my name be used with the information?What happens to the information I gave if I quit the study?Is there a written guarantee of privacy?

8. What do I have to do in the study?When did you start the study? How long will it last?How much of the study have you already done?Have there been any problems so far?Will I get treated the same as everyone else?What kinds of different treatments are offered in the study? Are thereboth real and fake treatments?

9. What will be left behind after the study is over?What will happen to the information people give? How will it be kept?What are you going to do with the results of the study?How will the public learn about the results? Will results be in placeswhere the public can see them?Are you going to send me a copy of the results? When?What other studies are you planning to do here?

The questions above are from a pamphlet developed by Project LinCS (LinkingCommunities and Scientists), Community Advisory Board (Durham, N.C.), andInvestigators (University of North Carolina Center for Health Promotion and DiseasePrevention) in cooperation with the Centers for Disease Control and Prevention, Atlanta,Ga. For copies of this brochure, contact the CDC National Prevention InformationNetwork at 1-800-458-5231.

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Resources

American Heart AssociationThe leading national organization devoted to heart health.7272 Greenville AvenueDallas, TX 752311-800-AHA-USA-1 (242-8721)www.heart.org

American Obesity AssociationThe national organization on obesity-related issues, from education toprevention to anti-discrimination work.1250 24th Street, NWSuite 300Washington, DC 20037www.obesity.org

American Stroke AssociationNational organization dedicated to stroke prevention, research, and treat-ment.7272 Greenville AvenueDallas, TX 752311-800-4-STROKE (478-7653)www.strokeassociation.org

ClinicalTrials.govA web-based resource for finding clinical trials in need of volunteers.www.clinicaltrials.gov

Combined Health Information DatabaseA web-based service that combines resources on health and disease topicsfrom several federal agencies. A service of the National Institutes ofHealth.chid.nih.gov/simple/simple.html

Healthy People 2010A nationwide health promotion and disease prevention campaign sponsored by the Department of Health and Human Services. One of the goals of the campaign is to reduce health disparities.

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Office of Disease Prevention and Health Promotion200 Independence Avenue, SW, Room 738GWashington, DC 20201www.healthypeople.govFor information on the “Healthy People 2010 Microgrant” program that financescommunity-based prevention activities: www.healthypeople.gov/implementa-tion/community/

MEDLINEplusA comprehensive source of health information provided by the National Libraryof Medicine.www.nlm.nih.gov/medlineplus/

National Center for Chronic Disease Prevention and Health PromotionSponsored by the CDC, the center promotes the transfer of research knowledgeinto actual prevention and treatment strategies. Provides information to the general public.Centers for Disease Control and Prevention4770 Buford Highway, NE, Mailstop K13Atlanta, GA 30341-3724770-488-5080www.cdc.gov/nccdphp/

National Heart, Lung, and Blood InstitutePart of the National Institutes of Health dedicated to learning about cardiovascular issues and lung-related illnesses.P.O. Box 30105Bethesda, MD 20824-0105301-592-8573/TTY: 240-629-3255www.nhlbi.nih.gov/

National Center on Minority Health and Health DisparitiesPromotes the health of racial and ethnic populations through research and edu-cation and through support of minority involvement in research careers.Affiliated with the National Institutes of Health.6707 Democracy Blvd., Suite 800MSC 5465Bethesda, MD 20892-5465301-402-1366/TTY: 301-451-9532ncmhd.nih.gov

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National Stroke AssociationGroup that offers information on stroke prevention and treatment and informa-tion on local resources.9707 E. Easter LaneEnglewood, CO 801121-800-STROKES (787-6537)www.stroke.org

Native American Research Centers for HealthResearch centers that link the Native American community with healthresearch and that work to increase the number of Native American scientistsand health professionals. National Institute of General Medical SciencesNational Institutes of Health45 Center Drive MSC 6200Bethesda, MD 20892-6200301-496-7301www.nigms.nih.gov

New York Online Access to HealthA searchable health information resource in English and Spanish.www.noah-health.org/index.html

Office for Human Research ProtectionsA source of information on the guidelines and ethics of research studies withhumans.Department of Health and Human Services1101 Wootton Parkway, Suite 200Rockville, MD 20852866-447-4777/301-496-7005www.hhs.gov/ohrp

Office of Minority Health Resource CenterServes as a national resource and referral service on minority health issues.Affiliated with the U.S. Department of Health and Human Services.P.O. Box 37337Washington, DC 20013-73371-800-444-6472www.omhrc.gov/omhrc/

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Shape Up America!Raises awareness of obesity as a health issue and provides evidence-based information and guidance on weight management.808 17th Street, NWSuite 600Washington, DC 20006www.shapeup.org

Weight-control Information NetworkProvides science-based information on weight control, obesity, physical activity,and related nutritional issues.1 WIN WayBethesda, MD 20892–36651-877-946-4627win.niddk.nih.gov

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BibliographyAgency for Healthcare Research and Quality. “AHRQ Study Finds Weight-lossSurgeries Quadrupled in Five Years.” July 12, 2005.www.ahrq.gov/news/press/pr2005/wtlosspr.htm

American Heart Association. “Heart and Stroke Facts.” 2003. heart.org/downloadable/heart/1056719919740HSFacts2003text.pdf

Appel, Lawrence J., MD, MPH; Michael W. Brands, PhD; Stephen R. Daniels, MD,PhD; Njeri Karanja, PhD; Patricia J. Elmer, PhD; Frank M. Sacks, MD. Hypertension.“Dietary Approaches to Prevent and Treat Hypertension.” Feb. 2006;47:296-308.

Calorie Control Council. “Lighten up and Get Moving.” www.caloriecontrol.org/exercalc.html

CBS News. "Fat Babies Face Health Problems." Feb. 3, 2002. www.cbsnews.com/sto-ries/2002/02/04/health/main328189.shtml.

CDC. “Preventing Obesity and Chronic Diseases Through Good Nutrition and Physical Activity.” July 2005.www.cdc.gov/nccdphp/publications/factsheets/Prevention/obesity.htm

Chiang, Mona. Science World. “Obesity: Battling a National Health Epidemic.” Feb. 7, 2005.

The Children's Hospital of Philadelphia. "Newborn's First Week May Be CriticalPeriod for Developing Obesity in Adulthood." April 18, 2005.www.prnewswire.com/cgi-bin/micro_stories.pl?ACCT=159681&TICK=CHOP&STORY=/www/story/04-18-2005/0003432937&EDATE=Apr+18,+2005.

Harvard School of Public Health. “Fats & Cholesterol.” 2006.www.hsph.harvard.edu/nutritionsource/fats.html

Kalb, Claudia and Anna Kuchment. Newsweek. “Saving Soul Food.” Jan. 30, 2006.

Kellow, Judith, RD. Weight Loss Resources. “Dining and Metabolism.” www.weight-lossresources.co.uk/calories/burning_calories/starvation.htm

Lambert, Craig. Harvard Magazine. “The Way We Eat Now.” May-June 2004.

Mann, Denise. WebMD. “The Latin Diet.” http://aolsvc.health.webmd.aol.com/con-tent/article/73/82025

Masters, Coco. "The Myth of Baby Fat." Time. May 5, 2006.time.blogs.com/daily_rx/2006/05/_the_myth_of_ba.html.

Mayo Clinic. “Fitness on a budget: Low-cost ideas for getting in shape.” Aug. 19, 2004.www.mayoclinic.com/health/fitness/HQ00694_D

National Center for Health Statistics. “Health, United States, 2005 With Chartbookon Trends in the Health of Americans.” Hyattsville, Maryland: 2005.

National Heart, Lung, and Blood Institute. NIH. “Tip Sheet: Eating Healthy withEthnic Food.” www.nhlbi.nih.gov/health/public/heart/obesity/lose_wt/eth_dine.htm

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National Institute of Diabetes and Digestive and Kidney Diseases. “Diet and ExerciseDramatically Delay Type 2 Diabetes: Diabetes Medication Metformin Also Effective.”www.niddk.nih.gov/welcome/releases/8_8_01.htm

—. “Your Digestive System and How It Works.”digestive.niddk.nih.gov/ddiseases/pubs/yrdd/

—. “Longitudinal Assessment of Bariatric Surgery Fact Sheet.” NIH Publication No.04-5573. June 2005.

—. “Lower Your Risk, Improve Your Health.” Jan. 1, 1990.health.yahoo.com/topic/weightloss/overview/article/niddk/weight_loss_wlc_risks1

—. “Understanding Adult Obesity.” NIH Publication No. 01-3680: October 2001.Updated March 2006.

Popcorn Board. “Understanding Calories.” www.popcorn.org/nutrition/calories/pccal-fax.cfm

Raloff, Janet. "Still Hungry? Fattening revelations-and new mysteries-about thehunger hormone." Science News Online. April 2, 2005. www.sciencenews.org/arti-cles/20050402/bob9.asp

Rand Corporation. “Cost Of Treatment For Obesity-Related Medical Problems GrowingDramatically” March 9, 2004.

Reaney, Patricia. Reuters. “Obesity, smoking speed up ageing.” June 14, 2005.

Stein, Rob. Washington Post. “Science Notebook: A Common Gene for Obesity.” April 17,2006. Page A06.

United States Department of Health and Human Services. “Key Recommendations forthe General Population, Dietary Guidelines for Americans 2005.” January 11, 2005.www.health.gov/dietaryguidelines/dga2005/recommendations.htm

University of Alabama Health System. “Dear Doctor Column.” (August 25, 2003).www.health.uab.edu/show.asp?durki=61705

University of California Davis Health System. “Obesity increasing among AsianAmericans.” Oct. 23, 2004.

University of Utah University Health Care. “A Healthier U—Health Calculators.”uuhsc.utah.edu/uuhsc/healthierU/calculator/bodyFatCal.cfm

Vincitorio, Mike. “Mike’s Calorie And Fat Gram Chart For 1000 Foods.” www.calo-riecountercharts.com/index.html

Willett, Walter C., M.D. Eat, Drink, and Be Healthy. New York: Simon and Schuster,2001.

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Glossary

ad·just·a·ble gas·tric band·ing:weight-loss surgery that reduces thestomach's opening.

ar·ter·ies: any of the muscular elas-tic tubes that form a branching sys-tem and that carry blood away fromthe heart to the cells, tissues, andorgans of the body.

an·ti·ox·i·dants: a substance, suchas vitamin E, vitamin C, or beta-carotene, thought to protect bodycells from some kinds of damage.

ar·thri·tis: inflammation of a joint,usually accompanied by pain,swelling, and stiffness, and resultingfrom infection, trauma, degenerativechanges, metabolic disturbances, orother causes.

bil·i·o·pan·cre·at·ic di·ver·sion:weight-loss surgery that removesmost of the stomach.

blood pres·sure: pressure of bloodagainst artery walls.

blood ves·sels: the pipelinesthrough which blood travels to allparts of the body.

bod·y fat: extra calories stored forlater use in the body.

bod·y fat per·cent·age: an estimateof how much of your body is made upof fat.

bod·y mass in·dex (BMI): a meas-ure of fatness that is calculatedusing height and weight. An idealbody mass index is 19, 20, or 21. Theformula for body mass index is:weight in pounds divided by heightin inches, divided by height in inchesagain, times 703.

cal·i·pers: tools that measure bodyfat in an area of the body.

cal·o·ries: units of energy-producingpotential equal to the amount of heatthat is contained in food and releasedupon oxidation by the body.

car·bo·hy·drates: foods that containsugars and starches.

car·di·o·vas·cu·lar: term thatdescribes the heart and blood vessels.

car·di·o·vas·cu·lar dis·ease: thecombination of disease of the bloodvessels and disease of the heart.

cho·les·ter·ol: a waxy substanceproduced by the body and taken inwith food. The body needs cholesterolfor functions such as making hormones, but too much can clogarteries and cause health problems.

chron·ic: long lasting and on going.

clin·i·cal tri·als: research testsusing people that are performed toevaluate the success of a medicaltreatment, medicine, or prevention

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strategy. A clinical trial usually isconducted only after the test has beensuccessful in the laboratory and onanimals.

co·lo·rec·tal can·cer: a malignancythat arises from the lining of eitherthe colon or the rectum. Cancers ofthe large intestine are the secondmost common form of cancer found inmales and females.

di·a·be·tes: a set of illnesses causedby improper amounts of glucose (aform of sugar found in the body) inthe blood.

di·ag·no·sis: a professional medicalopinion, based on an examination ofthe patient, about what is causingsymptoms of illness.

di·as·tol·ic: minimum pressure thatremains within the artery when theheart is at rest.

di·e·tar·y fat: fat found in food.

di·eth·yl·pro·pi·on: a short-termappetite suppressant.

gas·tric by·pass: weight-loss surgerythat re-routes the stomach.

genes: units of hereditary informa-tion contained in each cell of the body.

ge·net·ics: the field of science thatlooks at how genes are passed downfrom one generation to another toinfluence traits.

ge·net·ic pre·dis·po·si·tion: theterm for a person’s increased likeli-hood of developing some trait or ill-

ness because he or she carries certaingenes.

glu·cose: blood sugar.

gout: a painful buildup of uric acid inthe body.

health dis·par·i·ty: the unevenimpact of a health problem that mayoccur between groups of people.

heart at·tack: a failure of the heartto perform its job of pushing bloodthrough the blood vessels.

heart dis·ease: disease of the heart,the organ that pumps blood throughthe body. It is one of the possiblecomplications of high blood pressure.

height-weight growth chart: ameasurement doctors use to see if achild weighs too much for his or herheight.

high blood pres·sure: a condition inwhich blood is pushed through thebody’s blood vessels at greater forcethan normal. It can lead to tiredness,heart attack, stroke and other healthproblems. High blood pressure is alsoknown as hypertension.

hor·mone: a protein produced by anorgan of the body to trigger activity inother locations.

hy·per·ten·sion: the medical term forhigh blood pressure.

im·mune sys·tem: the coordinatedresponses of the body that serve toprotect it against outside invaderssuch as viruses and bacteria.

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Glossary

in·flam·ma·tion: a localized protec-tive reaction of tissue to irritation,injury, or infection, characterized bypain, redness, swelling, and some-times loss of function.

in·su·lin: a hormone released by thepancreas that triggers the opening ofbody cells to receive glucose.

in·su·lin re·sis·tance: actions bythe cells to oppose insulin, whichseeks to open the cells so that glucose may enter.

kid·ney dis·ease: a disease of thekidneys, the pair of organs that filterthe blood. The disease can lead tokidney failure. It is also called neu-ropathy. It is one of the possiblecomplications from high blood pressure.

kid·neys: the pair of organs thathave the job of filtering the blood.

lap·a·ro·scop·ic: a less invasivetype of surgery that uses a fiberopticinstrument.

mal·nu·tri·tion: poor nutritioncaused by an insufficient or poorlybalanced diet or faulty digestion orutilization of foods.

me·tab·o·lism: the series of chemi-cal changes that take place in anorganism, by means of which foodand other substances are changedinto energy and waste materials areeliminated.

mm Hg: abbreviation for millime-ters of mercury. It is used to expressmeasures of blood pressure. It refers

to the height to which the pressurein your blood vessels would push acolumn of mercury.

o·bese: suffering from obesity.

o·be·si·ty: the condition of being tooheavy for one’s height.

ob·struc·tive sleep ap·ne·a:a condition where a person stopsbreathing while asleep because of an obstruction in the airway.

or·li·stat: a diet drug that preventsfat absorption

os·te·o·po·ro·sis: a disease in whichthe bones become extremely porous,are subject to fracture, and healslowly, occurring especially inwomen following menopause andoften leading to curvature of thespine from vertebral collapse.

o·ver·weight: the condition ofweighing more than one should.

pan·cre·as: the organ of the bodythat produces insulin and other hor-mones.

pe·di·a·tri·cian: a specialist in thecare of babies and young children.

phen·di·met·ra·zine: a short-termappetite suppressant

phen·ter·mine: a diet drug thatkeeps you from feeling hungry.

po·tas·si·um: a mineral in thebody’s cells necessary for maintain-ing fluid balance. Good sources ofpotassium are bananas and orange

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juice. “Salt substitutes” usually con-tain potassium.

pros·tate can·cer: the second mostcommon malignancy in men. Mostcommonly seen in older men, with theage of 73 being the average age at thetime of diagnosis.

pro·tein: one of the body’s mainbuilding blocks. Protein is made bythe liver and comes from certain foodslike fish and beans.

pu·ber·ty: the stage of adolescence in which an individual becomes physiologically capable of sexualreproduction.

pulse: heartbeats per minute.

salt: common table salt or sodiumchloride.

sat·u·rat·ed fat·ty ac·ids: a fattyacid whose carbon chain cannot carryany more hydrogen; found chiefly inanimal fats.

sed·en·tar·y: accustomed to sitting or to taking little exercise.

si·bu·tra·mine: a diet drug thatmakes you feel full.

so·di·um: a mineral that can con-tribute to high blood pressure in somepeople. It is found in baking soda,some antacids, the food preservativeMSG (monosodium glutamate), amongother items.

starch·es: a naturally abundantnutrient carbohydrate found in theseeds, fruits, corn, potatoes, wheat,and rice.

stroke: damage to the blood vesselsin the brain because of loss of bloodflow, which can result in the inabilityto speak or move part of the body.

sup·ple·ments: something added tocomplete a thing, make up for a defi-ciency, or extend or strengthen thewhole, as in “dietary supplements.”

symp·tom: a sign of a problem, suchas a disease.

sys·tol·ic: maximum pressure in theartery produced as the heart contractsand blood begins to flow.

trans fat·ty ac·ids: fats that are badfor human health.

treat·ment plan: a plan put togetherby a doctor or team of health care professionals working with a patient.The patient is responsible for follow-ing the plan, with the goal of elimi-nating a disease or health condition or of reducing or delaying its complications.

un·sat·u·rat·ed fat·ty ac·ids: a fattyacid whose carbon chain can carryadditional hydrogen.

ver·ti·cal gas·tric band·ing: weight-loss surgery that reduces the openingto the stomach.

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Yolanda CuestaCuesta Multicultural Consulting

Yolanda GeorgeAmerican Association for the Advancement ofScience (AAAS)

Robert D. Goldman, PhDNorthwestern University Medical School

Max Gomez, PhDWNBC, Health & Science Editor

Beatrix (Betty) Ann Hamburg, MD Cornell University Medical College

Marcia HarringtonDistrict of Columbia Public Library

Constance Hendricks, PhDDean, Professor, School of Nursing, Hampton University

Eric Jolly, PhDEducation Development Center Inc. (EDC)

Betty LawrenceRochester Public Library, New York

Audrey Manley, MDPresident Emerita, Spelman College

Marsha Lakes Matyas, PhDThe American Physiological Society

Sandra NegroSenior Librarian, Wheaton Library,Maryland

Delores Parron, PhDScientific Advisor for Capacity Development,Office of the Director, National Institutes ofHealth

Joseph Perpich, MD, JDJ.G. Perpich, LLC

Marcy Pride, MLS, MADirector, Oyer Memorial Library Washington Bible College and Capital BibleSeminary, Lanham, Maryland

Josefina Tinajero, EdDAssociate Dean, College Of Education University of Texas at El Paso

Obesity ContentReviewers/Advisors

Henry L. Laws, MD, FACSFormer Director of Surgical Education,Carraway Methodist Medical CenterFormer Clinical Professor of Surgery,University of Alabama at Birmingham

Marie E. Latulippe, MS, RDSenior Project ManagerInternational Life Sciences Institute NorthAmerica, Washington, DC

Project Staff and ConsultantsShirley M. Malcom, PhDPrincipal Investigator

Maria Sosa, Co-Principal Investigator andProject Director

Kirstin Fearnley, Project Manager

Mary Chobot, PhD, Library Consultantand Project Evaluator

Ann Marie Williams, Art Director

Susan Mahoney and Associates, Janet Mednik, Writers

Betty Calinger, Editor

Heather Malcomson, Chickona Royster,Project Associates

Special thanks go to Nathan Bell, HarrietPickett, Catherine Baker, and Lisa Boesen fortheir assistance with the development of thisbook series.

Acknowledgements

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Photo Credits:Cover: Eyewire Images1: Mark Richards/Corbis2: Mark Harmel/Photo Researchers, Inc.3: ADAM4: Coneyl Jay/Photo Researchers, Inc.6: The National Women's Health Information Center7: Mitchell Gerber/Corbis8: Ken Hammond/USDA13: Scott Bauer/USDA14: Scott Bauer/USDA15: The National Women's Health Information Center17: ADAM19: ADAM20: Karen Kasmauski/Corbis23: Lawrence Migdale/Photo Researchers, Inc.24: Harry Mullen25: ADAM27: Russell Curtis/Photo Researchers, Inc.29: Karen Kasmauski/Corbis31: Carolyn A. McKeone/Photo Researchers, Inc.32: Iowa State University33: CDC34: Annie Griffiths Belt/Corbis35: Kirstin Fearnley36: Brian Bailey/Corbis37: MyPyramid.gov38: SSPL/The Image Works41: Laurent/Dielundama/Photo Researchers, Inc.43: ADAM45: Sarah Takagi47: Bruce Fritz/USDA48: Penni Gladstone/San Francisco Chronicle/Corbis49: Alix/Photo Researchers, Inc.52: Lawrence Migdale/Photo Researchers, Inc.55: David Grossman/Photo Researchers, Inc.56: Gabe Palmer/Corbis