SymptomsBy Mayo Clinic Staff
Obesity is diagnosed when your body mass index (BMI) is 30 or higher. Your body mass index is calculated by dividing your weight in kilograms (kg) by your height in meters (m) squared.
||Obese (Class I)
||Obese (Class II)
|40.0 and higher
||Extreme obesity (Class III)
For most people, BMI provides a reasonable estimate of body fat. However, BMI doesn't directly measure body fat, so some people, such as muscular athletes, may have a BMI in the obese category even though they don't have excess body fat. Ask your doctor if your BMI is a problem.
When to see a doctor
If you think you may be obese, and especially if you're concerned about weight-related health problems, see your doctor or health care provider. You and your provider can evaluate your health risks and discuss your weight-loss options.
June 10, 2015
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