text enlarger

Overweight/Obesity and Weight Control

BMI values for adults are interpreted based on a fixed number, regardless of age or sex, using the following guidelines:

Underweight:  BMI less than 18.5
Overweight:  BMI of 25.0 to 29.9
Obese:  BMI of 30.0 or more

100 million adult americans are overweight and risk serious disease

Nearly 100 million adults in America have a problem that puts them at increased risk of chronic disease: They are overweight or obese. Are you — or someone close to you — among them?

A person is considered obese if he or she weighs at least 20 percent more than the maximum healthy weight for his or her height. About three in 10 people in the United States are obese, and the condition is becoming increasingly common.

Obesity can cause many health problems due to the strain it puts on organs and joints. It increases the risk of some widespread and potentially fatal disorders such as diabetes, hypothyroidism, coronary artery disease, stroke and high blood pressure. It may also lead to psychological problems such as depression.

Causes of obesity

  • Overeating and a sedentary lifestyle
  • Hormonal disorders such as hypothyroidism (rare)
  • Corticosteroid drugs
  • Psychological problems

Are there complications?

  • Increased risk of various chronic health problems such as high blood pressure levels
  • Greater risk of gallstones
  • Greater risk of developing diabetes
  • Strains on the joints (osteoarthritis is common in obese people)
  • Sleep apnea (a respiratory disorder)

BMI and risk of Coronary Heart Disease (CHD) in men

  • In a study of British men, CHD incidence increased at BMIs above 22
  • An increase in one BMI unit is associated with a 10 percent increase in the rate of coronary events
  • Similar relationships have been shown in U.S. populations

Other overweight/obesity-related health complications


  • Twice as many women with a body mass index (BMI) greater than 29 had colon cancer as women with a BMI less than 21
  • A gain of more than 20 pounds, from age 18 to 40, doubles a woman’s risk of postmenopausal breast cancer
  • The risk of endometrial cancer is three times higher among women with a BMI of 30 or higher, compared to normal weight women


  • Twenty-seven percent of new cases of diabetes are attributable to weight gain of 11 pounds or more in adulthood
  • The relative risk of diabetes increases by about 25 percent for each additional unit of BMI over 22
  • Diabetes is associated with long-term complications that affect almost every major part of the body; it can cause blindness, heart disease, stroke, kidney failure, nerve damage and sometimes requires amputation(s)


  • In a study of middle-aged women, every 2.2 pound increase in weight was associated with a 9.13 percent increase in the risk of developing osteoarthritis in the knees
  • A drop in BMI of two units or more during a 10-year period decreased the odds for developing knee osteoarthritis by more than 50 percent
  • The risk of endometrial cancer is three times higher among women with a BMI of 30 or higher, compared to normal weight women