What is the prevalence of overweight and obesity among U.S. adults?

Results from the 2003-2004 National Health and Nutrition Examination Survey (NHANES), using measured heights and weights, indicate that an estimated 66 percent of U.S. adults are either overweight or obese.

To read more about American adult overweight and obesity trends, visit

• NHANES Data on the Prevalence of Overweight and Obesity Among Adults: United States, 2003-2004
  National Center for Health Statistics
• Obesity Trends
  CDC, Nutrition and Physical Activity

What is the prevalence of overweight among U.S. children?

Results from the 2003-2004 National Health and Nutrition Examination Survey (NHANES), using measured heights and weights, indicate that an estimated 17 percent of children and adolescents ages 2-19 years are overweight.

To read more about childhood and adolescent overweight, visit

• Prevalence of Overweight Among Children and Adolescents: United States, 2003-2004
  National Center for Health Statistics (NHANES)
• The Surgeon General's Call to Action to Prevent and Decrease Overweight and Obesity: Overweight in Children and Adolescents

What is the difference between being overweight and being obese?

Overweight and obesity are both labels for ranges of weight that are greater than what is generally considered healthy for a given height. The terms also identify ranges of weight that have been shown to increase the likelihood of certain diseases and other health problems.

For adults, overweight and obesity ranges are determined by using weight and height to calculate a number called the "body mass index" (BMI).

• An adult who has a BMI between 25 and 29.9 is considered overweight.
• An adult who has a BMI of 30 or higher is considered obese.

See the following table for an example.

It is important to remember that although BMI correlates with the amount of body fat, BMI does not directly measure body fat. As a result, some people, such as athletes, may have a BMI that identifies them as overweight even though they do not have excess body fat. For more information about BMI, visit Body Mass Index. 

For children and teens, BMI ranges above a normal weight have different labels (at risk of overweight and overweight). Additionally, BMI ranges for children and teens are defined so that they take into account normal differences in body fat between boys and girls and differences in body fat at various ages. For more information about BMI for children and teens (also called BMI-for-age), visit BMI for Children and Teens. 

What are some of the factors that contribute to overweight and obesity?

Researchers have found that several factors can contribute to the likelihood of someone's becoming overweight or obese.

• Behaviors. What people eat and their level of physical activity help determine whether they will gain weight. A number of factors can influence diet and physical activity, including personal characteristics of the individual, the individual's environment, cultural attitudes, and financial situation.
• Genetics. Heredity plays a large role in determining how susceptible people are to becoming overweight or obese. Genes can influence how the body burns calories for energy and how the body stores fat.

To read more about the factors that can contribute to overweight and obesity, visit

• The Surgeon General's Call to Action to Prevent and Decrease Overweight and Obesity, Overweight and Obesity, At a Glance
• The Surgeon General's Call to Action to Prevent and Decrease Overweight and Obesity, Overweight in Children and Adolescents
• Obesity and Genetics: A Public Health Perspective
  CDC, Office of Genomics and Disease Prevention

How does being overweight or obese affect a person's health?

When people are or overweight or obese, they are more likely to develop health problems such as the following:

• Hypertension
• Dyslipidemia (for example, high total cholesterol or high levels of triglycerides)
• Type 2 diabetes
• Coronary heart disease
• Stroke
• Gallbladder disease
• Osteoarthritis
• Sleep apnea and respiratory problems
• Some cancers (endometrial, breast, and colon)

The more overweight a person is, the more likely that person is to have health problems. Among people who are overweight and obese, weight loss can help reduce the chances of developing these health problems. Studies show that if a person is overweight or obese, reducing body weight by 5 percent to 10 percent can improve one's health.

To read more about how being overweight or obese can affect health, visit

• Do You Know the Health Risks of Being Overweight?
  National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
• The Surgeon General's Call to Action to Prevent and Decrease Overweight and Obesity, Overweight and Obesity: Health Consequences

What can be done about this major public health problem?

The Surgeon General has called for a broad approach to help prevent and reduce obesity. The Surgeon General has identified 15 activities as national priorities.

To read more about what can be done, visit

• The Surgeon General's Call to Action to Prevent and Decrease Overweight and Obesity: A Vision for the Future
• The Surgeon General's Call to Action to Prevent and Decrease Overweight and Obesity, Overweight and Obesity: What You Can Do

What are the costs associated with overweight and obesity?

According to The Surgeon General's Call to Action to Prevent and Decrease Overweight and Obesity, the cost of obesity in the United States in 2000 was more than $117 billion ($61 billion direct and $56 billion indirect).

To read more about the costs of overweight and obesity, visit

• The Surgeon General's Call to Action to Prevent and Decrease Overweight and Obesity: Economic Consequences
• The Surgeon General's Call to Action to Prevent and Decrease Obesity and Overweight: Overweight and Obesity: What You Can Do

What is being done by CDC to address the problem of overweight and obesity?

CDC and its partners work in a variety of ways to prevent and control obesity. A few examples of these efforts include:

• CDC funds a number of programs in state health departments, communities, and schools. For example, CDC's Division of Nutrition, Physical Activity and Obesity funds state health department programs to help develop and carry out targeted nutrition and physical activity interventions to prevent obesity and other chronic diseases. CDC also provides consultation, technical assistance, and training to use programs.
• CDC funds other programs which have physical activity, nutrition, and obesity components, such as STEPS to a HealthierUS and Coordinated School Health Programs.
• CDC monitors weight status or related behaviors, such as diet and physical activity. These efforts include the Behavioral Risk Factor Surveillance System (BRFSS), National Health and Nutrition Examination Survey (NHANES), Pediatric Nutrition Surveillance System (PedNSS), and Youth Risk Behavior Surveillance System (YRBSS).
• CDC funds and conducts research on the individual and environmental factors that determine weight status and related health effects, on strategies and interventions to change weight or weight-related behaviors, and on the economic impact of overweight and obesity.
• CDC provides growth charts that are used to identify weight problems among young people and provides training on the use of those charts.

To find out more about these efforts, visit

• Physical Activity and Good Nutrition: Essential Elements to Prevent Chronic Diseases and Obesity 2004, At A Glance
  CDC, Nutrition and Physical Activity
• State-Based Nutrition and Physical Activity Program to Prevent Obesity and Other Chronic Diseases
  CDC, Nutrition and Physical Activity
• STEPS to a HealthierUS
• 2000 CDC Growth Charts: United States
• Surveillance systems:
  • Behavioral Risk Factor Surveillance System (BRFSS)
  • National Health and Nutrition Examination Survey (NHANES)
  • Pediatric Nutrition Surveillance System (PedNSS)
  • Youth Risk Behavior Surveillance System (YRBSS)

What are some suggestions for losing weight?

Most experts recommend that someone attempting to lose a large amount of weight consult with a personal physician or health care professional before beginning a weight-loss program. The Surgeon General's Healthy Weight Advice for Consumers makes the following general recommendations:

• Aim for a healthy weight. People who need to lose weight should do so gradually, at a rate of one-half to two pounds per week.
• Be active. The safest and most effective way to lose weight is to reduce calories and increase physical activity.
• Eat well. Select sensible portion sizes and follow the Dietary Guidelines for Americans.

For more information about losing weight, visit

• Dietary Guidelines for Americans 2005
  Department of Health and Human Services (HHS) and the Department of Agriculture (USDA)
• Aim for a Healthy Weight
  National Institutes of Health (NIH), National Heart, Lung, and Blood Institute (NHLBI)
• Weight-control Information Network: Publications
  National Institutes of Health (NIH), National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), Weight-control Information Network
• The Surgeon General's Call to Action to Prevent and Decrease Overweight and Obesity: Surgeon General's Healthy Weight Advice for Consumers
  

How can physical activity help prevent overweight and obesity?

Physical activity, along with a healthy diet, plays an important role in the prevention of overweight and obesity (USDHHS, 2001). In order to maintain a stable weight, a person needs to expend the same amount of calories as he or she consumes.

Although the body burns calories for everyday functions such as breathing, digestion, and routine daily activities, many people consume more calories than they need for these functions each day. A good way to burn off extra calories and prevent weight gain is to engage in regular physical activity beyond routine activities.

The Dietary Guidelines for Americans 2005 offers the following example of the balance between consuming and using calories:

If you eat 100 more food calories a day than you burn, you'll gain about 1 pound in a month. That's about 10 pounds in a year. The bottom line is that to lose weight, it's important to reduce calories and increase physical activity.