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    Body Mass Index (BMI)

    Body Mass Index (BMI)

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    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 diseases footnote 1
    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



    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.


    ByHealthwise Staff
    Primary Medical Reviewer E. Gregory Thompson, MD - Internal Medicine
    Specialist Medical Reviewer Rhonda O'Brien, MS, RD, CDE - Certified Diabetes Educator

    Current as ofOctober 13, 2016

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