Understanding Adult 

Overweight and Obesity

U.S. Department of Health 

and Human Services

 WIN Weight-control Information Network

When we eat more calories than we burn, our 

bodies store this extra energy as fat. While a few 

extra pounds may not seem like a big deal, they 

can increase your chances of having high blood 

pressure and high blood sugar. These conditions 

may lead to serious health problems, including 

heart disease, stroke, type 2 diabetes, and 

certain cancers.

Today, more than two-thirds of adults in the United 

States are considered to be overweight or obese. 

More than one-third of adults have obesity. This 

fact sheet will help you find out if you may be at 

risk of developing weight-related health problems. 

It will also explain how overweight and obesity are 

treated and give you ideas for improving your 

health at any weight.

How can I tell if I am at a normal weight?

Body mass index (BMI) is one way to tell whether 

you are at a normal weight, overweight, or obese. The 

BMI measures your weight in relation to your height. 

The BMI table on the next page will help you to 

find your BMI score. Find your height in inches 

in the left column labeled “Height.” Move across 

the row to your weight. The number at the top of 

the column is the BMI for that height and weight. 

Pounds are rounded off. You may also go to the 

Resources section at the end of this booklet for a 

link to an online tool for measuring BMI.

A BMI of 18.5 to 24.9 is in the normal range. 

A person with a BMI of 25 to 29.9 is considered 

overweight, and someone with a BMI of 30 or 

greater is considered obese.

However, because BMI doesn’t measure actual 

body fat, a person who is very muscular, like a 

bodybuilder, may have a high BMI without having 

a lot of body fat. Please review your findings with 

your health care provider if your BMI is outside 

of the normal range.

Why do people gain weight?

Our bodies need calories (energy) to keep us alive 

and active. But to maintain weight we need to 

balance the energy we take in with the energy we 

use. When a person eats and drinks more calories 

than he or she burns, the energy balance tips toward 

weight gain, overweight, and obesity. The tipping 

Does my body shape matter?

Health care providers are concerned not only 

with how much body fat a person has, but 

where the fat is located on the body. 

 Women tend to collect fat in their hips and 

buttocks, giving them a “pear” shape. 

 Men usually build up fat around their 

bellies, giving them more of an “apple” 

shape. 

 Of course, some men are pear-shaped and 

some women are apple-shaped, especially 

after menopause.

Extra fat around your midsection may put 

you at greater risk for type 2 diabetes, heart 

disease, and other health problems—even if 

you have a normal weight. Your provider can 

help you assess your risk.

(continued on page 3)
Table 1. Body Mass Index Table 

To use the table, find the appropriate height in the left-hand column labeled Height. Move across to a given weight (in pounds). The number at the top of the column is the BMI at that height and weight. Pounds have been rounded off.

Normal Overweight Obese Extreme Obesity

BMI 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54

Height

(inches) Body Weight (pounds)

58 91 96 100 105 110 115 119 124 129 134 138 143 148 153 158 162 167 172 177 181 186 191 196 201 205 210 215 220 224 229 234 239 244 248 253 258

59 94 99 104 109 114 119 124 128 133 138 143 148 153 158 163 168 173 178 183 188 193 198 203 208 212 217 222 227 232 237 242 247 252 257 262 267

60 97 102 107 112 118 123 128 133 138 143 148 153 158 163 168 174 179 184 189 194 199 204 209 215 220 225 230 235 240 245 250 255 261 266 271 276

61 100 106 111 116 122 127 132 137 143 148 153 158 164 169 174 180 185 190 195 201 206 211 217 222 227 232 238 243 248 254 259 264 269 275 280 285

62 104 109 115 120 126 131 136 142 147 153 158 164 169 175 180 186 191 196 202 207 213 218 224 229 235 240 246 251 256 262 267 273 278 284 289 295

63 107 113 118 124 130 135 141 146 152 158 163 169 175 180 186 191 197 203 208 214 220 225 231 237 242 248 254 259 265 270 278 282 287 293 299 304

64 110 116 122 128 134 140 145 151 157 163 169 174 180 186 192 197 204 209 215 221 227 232 238 244 250 256 262 267 273 279 285 291 296 302 308 314

65 114 120 126 132 138 144 150 156 162 168 174 180 186 192 198 204 210 216 222 228 234 240 246 252 258 264 270 276 282 288 294 300 306 312 318 324

66 118 124 130 136 142 148 155 161 167 173 179 186 192 198 204 210 216 223 229 235 241 247 253 260 266 272 278 284 291 297 303 309 315 322 328 334

67 121 127 134 140 146 153 159 166 172 178 185 191 198 204 211 217 223 230 236 242 249 255 261 268 274 280 287 293 299 306 312 319 325 331 338 344

68 125 131 138 144 151 158 164 171 177 184 190 197 203 210 216 223 230 236 243 249 256 262 269 276 282 289 295 302 308 315 322 328 335 341 348 354

69 128 135 142 149 155 162 169 176 182 189 196 203 209 216 223 230 236 243 250 257 263 270 277 284 291 297 304 311 318 324 331 338 345 351 358 365

70 132 139 146 153 160 167 174 181 188 195 202 209 216 222 229 236 243 250 257 264 271 278 285 292 299 306 313 320 327 334 341 348 355 362 369 376

71 136 143 150 157 165 172 179 186 193 200 208 215 222 229 236 243 250 257 265 272 279 286 293 301 308 315 322 329 338 343 351 358 365 372 379 386

72 140 147 154 162 169 177 184 191 199 206 213 221 228 235 242 250 258 265 272 279 287 294 302 309 316 324 331 338 346 353 361 368 375 383 390 397

73 144 151 159 166 174 182 189 197 204 212 219 227 235 242 250 257 265 272 280 288 295 302 310 318 325 333 340 348 355 363 371 378 386 393 401 408

74 148 155 163 171 179 186 194 202 210 218 225 233 241 249 256 264 272 280 287 295 303 311 319 326 334 342 350 358 365 373 381 389 396 404 412 420

75 152 160 168 176 184 192 200 208 216 224 232 240 248 256 264 272 279 287 295 303 311 319 327 335 343 351 359 367 375 383 391 399 407 415 423 431

76 156 164 172 180 189 197 205 213 221 230 238 246 254 263 271 279 287 295 304 312 320 328 336 344 353 361 369 377 385 394 402 410 418 426 435 443

Source: Adapted from Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults. The Evidence Report. NIH Publication No. 98-4083: National Heart, Lung, and Blood Institute; 1998.
3

point at which the calories coming in and the calories 

going out become out of balance and lead to weight 

gain may differ from one person to another. 

What other factors are involved?

Your genes, the world around you, and other 

factors may all affect weight gain. Learn how to 

address these factors in the section “How can I 

improve my health?”

Family

Research shows that obesity tends to run in 

families, suggesting that genes may contribute 

to obesity. Families also share diet and lifestyle 

habits that may affect weight. However, it is 

possible to manage your weight even if obesity 

is common in your family.

(continued from page 1)

The World around You

Where people live, play, and work may also strongly 

affect their weight. Consider the fact that obesity 

rates were lower 30 years ago. Since that time, our 

genetic make-up hasn’t changed, but our world has.

The world around us affects access to healthy foods 

and places to walk and be active in many ways:

■ Many people drive rather than walk.

■ Living in areas without sidewalks or safe 

places to exercise may make it tough to be 

more active. 

■ Many people eat out or get takeout instead 

of cooking, which may lead to eating more 

calories.

■ Most vending machines do not offer lowcalorie, low-fat snacks. 

Overweight and obesity affect people in all income 

ranges. But people who live in low-income areas 

may face even greater barriers to eating healthy 

foods and being active than other people. Highcalorie processed foods often cost less than healthier 

options, such as fruits and vegetables. There also 

may be few safe, free, or low-cost places nearby to 

be active on a regular basis. These factors may 

contribute to weight gain.

Culture

A person’s culture may also affect weight: 

■ Some cultures have foods with a lot of fat or 

sugar, making it hard to manage weight. 

■ Family events at which people eat large 

amounts of food may make it tough to 

control portions.

Sleep

Research suggests that lack of sleep is linked to 

overweight and obesity. Recent studies have found 

that sleeping less may make it harder to lose weight. 

In these studies, adults who were trying to lose 

weight and who slept less ate more calories and 

snacked more. 

For more on how obesity and sleep are related, 

see the Resources section at the end of this fact 

sheet for a link to the WIN fact sheet Do You 

Know Some of the Health Risks of Being Overweight?

Medicine

Certain drugs may cause weight gain. Steroids and 

some drugs to treat depression or other mental health 
4

problems may make you burn calories more slowly 

or feel hungry. Be sure your health care provider 

knows all the medicines you are taking (including 

over-the-counter drugs and dietary supplements). 

He or she may suggest another medicine that has 

less effect on weight.

What problems are linked to excess weight?

Weighing too much may increase the risk for several 

health problems. It also may contribute to emotional 

and social problems.

Health Risks

Type 2 diabetes, heart disease, high blood pressure, 

stroke, kidney disease, and certain cancers are some 

of the diseases linked to excess weight. Obese men 

are more likely than other men to develop cancer 

of the colon, rectum, or prostate. Obese women are 

more likely than other women to develop cancer 

of the breast (after menopause), gallbladder, uterus, 

or cervix. Cancer of the esophagus (the tube that 

carries food and liquids to the stomach) may also 

be linked to obesity.

Other diseases and health problems linked to 

excess weight include

■ breathing problems, including sleep apnea

■ fatty liver disease (also called nonalcoholic 

steatohepatitis or NASH)1

■ gallbladder disease and gallstones

■ pregnancy problems, such as gestational 

diabetes (high blood sugar during pregnancy), 

high blood pressure, and increased risk for 

cesarean section (C-section) 

Emotional and Social Effects

Excess weight may also contribute to emotional 

suffering. Physical beauty and how a person looks 

are highly valued in society. People who may not 

fit society’s view of beauty because of their weight 

may be seen as less attractive.

1 For more information on NASH, see the listing in the 

Resources section for the National Digestive Diseases 

Information Clearinghouse.

Also, because some people in our culture may view 

a person with obesity as lacking willpower, people 

with obesity may face limited options in the job 

market, at school, and in social situations. They 

may feel rejected, ashamed, or depressed.

Who should lose weight?

Health care providers generally agree that people 

who are considered to be obese (have a BMI of 30 

or greater) may improve their health by losing weight. 

If you are overweight (BMI between 25 and 29.9), 

experts recommend that you avoid gaining any extra 

weight. If you are overweight and have other risk 

factors (see below), losing weight may reduce these 

risks. Experts recommend you try to lose weight if 

you have two or more of the following:

■ Family history of certain chronic diseases. If you 

have close relatives who have had diseases such 

as heart disease or diabetes, you may be more 

likely to develop these problems.

■ Pre-existing medical problems. High blood 

pressure, high LDL (bad) cholesterol levels, 

low HDL (good) cholesterol levels, high 

triglycerides, and high blood sugar (prediabetes 

or diabetes) are all warning signs of some diseases 

linked to obesity.

■ Large waist size. Men who have waist sizes 

greater than 40 inches and women who have 

waist sizes greater than 35 inches are at higher 

risk of diabetes, unhealthy blood fats (high 

cholesterol and triglycerides), high blood 

pressure, and heart disease.

Fortunately, losing even a small amount of weight 

can help improve your health. This weight loss 

may lower your blood pressure and improve other 

risk factors. 

For example, research shows that people at high risk 

for type 2 diabetes who lose a modest amount of 

weight and increase their physical activity may 

prevent or delay type 2 diabetes. For more 

information, see the listing in the Resources section 

for the National Diabetes Education Program.
5

How are overweight and obesity treated?

The best way to control your weight may depend 

on how much excess weight you have, your overall 

health, and how ready you are to change your eating 

and physical activity habits. In some cases, if lifestyle 

changes do not lead to enough weight loss to improve 

your health, doctors may recommend additional 

treatment, including weight-loss drugs. 

In some cases of extreme obesity, doctors may 

recommend bariatric surgery. For more information 

on bariatric surgery, see the WIN fact sheet Bariatric 

Surgery for Severe Obesity, listed in the Resources 

section. 

How can I improve my health?

Although you cannot change your genes, you can 

work on changing your eating habits, levels of 

physical activity, and other factors. Try the ideas 

below.

Get regular physical activity

Try these tips for starting or maintaining an 

exercise program:

■ Get at least 150 minutes (2 1⁄2 hours) of 

moderately intense aerobic activity each 

week that raises your heart rate and makes 

you sweat. Brisk walking, biking (with a 

helmet), swimming, and playing tennis or 

basketball are fun choices that you can do 

with others for support. 

■ You can spread the 150 minutes out in short 

spurts over the week. Do house or yard chores 

briskly, walk the dog at a quick pace, or dance 

to your favorite music for at least 10 minutes 

at a time.

■ Aim for 300 minutes (5 hours) of aerobic 

activity a week to prevent gradual weight 

gain in adulthood. If you are at a healthy 

weight now but used to be overweight or obese, 

experts encourage 60 to 90 minutes of exercise 

a day to keep the weight off.

Most adults don’t need to see their doctor before 

starting a physical activity program. However, 

those who should see a doctor include men 

older than 40 and women older than 50 who 

plan a vigorous program or who have either a 

serious health condition or risk factors for a 

serious health condition. 

Eat better

Eating healthy foods has vital health benefits, too, 

including weight loss. To start eating better, try 

these tips:

■ Eat the rainbow. Make half of what’s on your 

plate fruit and vegetables.

■ Replace refined grains with whole grains, like 

oatmeal, whole wheat bread, and brown rice.

■ Get your protein from healthy sources, like 

seafood, lean meats, poultry, eggs, beans, 

unsalted nuts, and seeds.

■ Instead of sugary drinks, choose unsweetened 

tea, low-fat milk, or water.

Remember, weight control is a lifelong effort. 

Starting now with small steps may improve your 

health. A healthy eating plan and regular physical 

activity can be steps to a healthier you.
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Research

The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) 

conducts and supports a broad range of basic and clinical obesity research. More 

information about obesity research is available at http://www.obesityresearch.nih.gov.

Participants in clinical trials can play a more active role in their own health care, 

gain access to new research treatments before they are widely available, and 

help others by contributing to medical research. For more information, visit 

http://www.clinicaltrials.gov.

Resources

Additional Reading from the Weight-control Information Network

For more information on topics related to healthy eating, barriers to physical 

activity, portion control, and eating and physical activity myths, refer to these WIN 

publications. All are available online at http://win.niddk.nih.gov/publications.

■ Active at Any Size explains the benefits of regular physical activity and describes 

activities that people who are overweight or obese can enjoy safely.

■ Bariatric Surgery for Severe Obesity explains how this operation on the stomach 

and/or intestines helps patients with extreme obesity to lose weight. Patients may 

use this fact sheet to talk about this option with their health care providers.

■ Do You Know Some of the Health Risks of Being Overweight? explains the 

harmful effects of being overweight and the benefits of losing weight.

■ Weight Loss for Life discusses the benefits of weight loss and helps readers 

plan for healthy eating and regular physical activity. This brochure also compares 

different types of weight-loss programs to help readers choose programs that are 

best for them.

Additional Resources

■ 2008 Physical Activity Guidelines for Americans

http://www.health.gov/paguidelines/guidelines/default.aspx

■ Body Mass Index Online Calculator

National Heart, Lung, and Blood Institute

http://www.nhlbisupport.com/bmi

■ Dietary Guidelines for Americans, 2010

http://health.gov/dietaryguidelines

■ National Diabetes Education Program

http://www.yourdiabetesinfo.org

■ National Digestive Diseases Information Clearinghouse

Information on NASH

http://www.digestive.niddk.nih.gov/ddiseases/pubs/nash/index.htm

■ National Kidney Disease Education Program

http://nkdep.nih.gov

Weight-control 

Information Network

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Bethesda, MD 20892–3665

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Fax: 202–828–1028

Email: win@info.niddk.nih.gov

Internet: 

http://www.win.niddk.nih.gov

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The Weight-control Information 

Network (WIN) is a national 

information service of the National 

Institute of Diabetes and Digestive 

and Kidney Diseases (NIDDK), part 

of the National Institutes of Health 

(NIH). WIN provides the general 

public, health professionals, and the 

media with science-based, up-to-date, 

culturally relevant materials and tips. 

Topics include healthy eating, barriers 

to physical activity, portion control, and 

eating and physical activity myths. 

Publications produced by WIN are 

carefully reviewed by both NIDDK 

scientists and outside experts. This fact 

sheet was also reviewed by Delia Smith 

West, Ph.D., Professor, University of 

Arkansas for Medical Sciences. 

Inclusion of resources is for information 

only and does not imply endorsement 

by NIDDK or WIN.

This publication is not copyrighted. 

WIN encourages you to copy and share 

as many copies as desired.

This publication is also available at 

http://www.win.niddk.nih.gov.

Photo, page 3: Sierra Faye Mitchell

Photo, page 5: Centers for Disease 

Control and Prevention/Amanda Mills

NIH Publication No. 06–3680

November 2008

Updated December 2012

NIH...Turning Discovery Into Health®