For adults, overweight and obesity ranges are determined by using weight and height to calculate a number called the "body mass index" (BMI). BMI is used because, for most people, it correlates with their amount of body fat.
- An adult who has a BMI between 25 and 29.9 is overweight
- An adult who has a BMI of 30 or higher is obese.
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.
The defining characteristic in both overweight and obese people is excess body fat. The difference is a matter of degree.
Healthcare professionals use a simple calculation called the body mass index (BMI) to determine body weight relative to height. In adults, the BMI calculation strongly correlates with total body fat content in adults. Overweight is defined as having a BMI between 25 and 29.9. Obesity is defined as having a BMI of 30 or more.
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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.