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Which BMI level is classified as obesity in adults?

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Close-up of hands using a measuring tape to measure the waist circumference of an obese man wearing a white shirt and beige pants. — obesity The excessive accumulation of body fat can cause serious medical conditions.

For adults aged 20 and older, a Body Mass Index (BMI) of 30.0 or higher is classified as obesity.12

It is important to note that while BMI is a widely used clinical standard, it is an indirect estimate of body fat and does not account for individual variations in muscle mass, bone density, or fat distribution. Because of these limitations, the American Medical Association has advised healthcare professionals not to rely solely on BMI when assessing a patient's health. Researchers are currently exploring more comprehensive diagnostic tools, such as waist circumference and body composition analysis, to provide a more accurate picture of metabolic health.12