Obesity is a complex disease in which having too much body fat increases a person's risk for developing other health problems. Obesity generally is measured by body mass index (BMI), a calculation that shows weight in relation to height.

As BMI increases, the risk of some diseases increases. A BMI of 30 or above is considered obese in adults, which means a person is at a higher risk for certain diseases, including heart disease, high blood pressure, and coronary artery disease (CAD). If you are Asian, your health may be at risk with a lower BMI. But BMI is only one of many factors used to predict the risk of developing a disease.

To fit the medical definition of obesity, the excess weight must come from having too much body fat. Athletes may have a BMI over 30, but because their weight is due to muscle, not fat, they are not considered obese.

The location of body fat is important. If fat accumulates mostly around the abdomen (central obesity, sometimes called apple-shaped), a person is at greater risk for type 2 diabetes, high blood pressure, high cholesterol, and CAD than people who are lean or people who have fat around the hips (peripheral obesity, sometimes called pear-shaped).

Last Updated: April 16, 2009

Author: Jeannette Curtis

Medical Review: Caroline S. Rhoads, MD - Internal Medicine & Matthew I. Kim, MD - Endocrinology & Metabolism

related physicians

related services

Bon Secours International| Sisters of Bon Secours USA| Bon Secours Health System

This information does not replace the advice of a doctor. Healthwise disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Privacy Policy. How this information was developed to help you make better health decisions.

© 1995-2010 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.