Body Mass Index (BMI) definition

A number that represents your weight in relation to your height and used as a general guide to categorize you as: underweight, normal weight, overweight, obese, morbidly obese.

Your BMI is determined by the following equation: 703 x [body weight (lbs)/height2 (inches)]

BMI Categories
  • If your BMI is less than 18.5, you’re considered underweight.
  • If your BMI is 18.5 – 24.9, you’re considered normal weight.
  • If your BMI is 25 – 29.9 you’re considered overweight.
  • If your BMI is 30 – 39.9, you’re considered obese.
  • If your BMI is 40 or more, you’re considered extremely obese.

If your BMI is 25 or more (overweight or obese), you are considered at risk for developing high blood pressure, type 2 diabetes, heart disease, and other diseases. In general, the higher your BMI, the greater your risk.

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