What is my Body Mass Index (BMI)?
Your Body Mass Index (BMI) is an estimate of your body fat, based on your height and weight.
Category BMI range – kg/m2
Starvation less than 14.9
Underweight from 15 to 18.4
Normal from 18.5 to 22.9
Overweight from 23 to 27.5
Obese from 27.6 to 40
Morbidly Obese greater than 40
The higher your BMI, the higher your risk of developing such conditions as heart disease, high blood pressure, sleep apnea, and type 2 diabetes.
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What Are the Risks Associated With Being Overweight or Obese?
People who are overweight (defined as a BMI between 25.0 and 29.9) or obese (defined as a BMI greater than or equal to 30) are at increased risk for developing a number of medical conditions, including the following:
• High blood pressure (hypertension)
• Heart disease
• Stroke
• High cholesterol or other lipid disorders
• Type 2 diabetes
• Certain cancers (endometrial, breast, and colon)
• Sleep apnea and respiratory problems
• Osteoarthritis
• Gallbladder disease
• Fatty liver disease.
​H​ow reliable is BMI as an indicator of body fatness?
The correlation between the BMI number and body fatness is fairly strong; however the correlation varies by sex, race, and age. These variations include the following examples:
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At the same BMI, women tend to have more body fat than men.
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At the same BMI, older people on average, tend to have more body fat than younger adults.
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Highly trained athletes may have a high BMI because of increased muscularity rather than increased body fatness.
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It is important to remember that BMI is only one factor related to risk for disease. For assessing someone's likelihood of developing overweight or obesity-related diseases, the National Heart, Lung, and Blood Institute guidelines recommend looking at two other predictors:
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​The individual's waist circumference (because abdominal fat is a predictor of risk for obesity-related diseases).
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Other risk factors the individual has for diseases and conditions associated with obesity (for example, high blood pressure or physical inactivity).
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