More than half of the U.S. population is overweight. But being obese is different from being overweight. An individual is considered obese when weight is 20% (25% in women) or more over the maximum desirable for their height. When an adult is more than 100 pounds overweight, it is considered morbid obesity.
Obesity is also defined as a BMI (body mass index) over 30 kg/m2. Patients with a BMI between 25 and 29.9 are considered overweight, but not obese. See also diet and calories.