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Body Mass Index (BMI)

Topic Overview

Your body mass index (BMI) and waist size affect your risk of type 2 diabetes, high blood pressure, high cholesterol, and coronary artery disease. The following table shows the risk.

Body mass index (BMI) and the risk for diseases1
Classification BMI Waist size and relative risk

Men: less than 40 in. (102 cm)

Women: less than 35 in. (88 cm)

Men: 40 in. (102 cm) or more

Women: 35 in. (88 cm) or more

Normal 18.5–24.9 Increased risk
Overweight 25–29.9 Increased risk High risk
Obesity I 30–34.9 High risk Very high risk
Obesity II 35–39.9 Very high risk Very high risk
Obesity III (extreme) 40 or above Extremely high risk Extremely high risk

For Asian people, each risk category may include lower BMIs than those listed in the table.

A BMI under 18.5 is considered unhealthy. There is risk that you are not getting sufficient nutrition (malnutrition). Complications of malnutrition include anemia, nutrient deficiency, heart irregularities, loss of menstrual periods in women (amenorrhea), cavities, and osteoporosis.

Related Information

References

Citations

  1. National Heart, Lung, and Blood Institute, National Institutes of Health (2000). The Practical Guide: Identification, Evaluation, and Treatment of Overweight and Obesity in Adults (NIH Publication No. 00-4084). Available online: http://www.nhlbi.nih.gov/guidelines/obesity/prctgd_c.pdf.

Credits

By Healthwise Staff
Primary Medical Reviewer E. Gregory Thompson, MD - Internal Medicine
Specialist Medical Reviewer Rhonda O'Brien, MS, RD, CDE - Certified Diabetes Educator
Last Revised May 25, 2011

This information does not replace the advice of a doctor. Healthwise, Incorporated 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. How this information was developed to help you make better health decisions.

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