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    Body Mass Index (BMI)

    Body Mass Index (BMI)



    Topic Overview

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

    Body mass index (BMI) and the risk for diseases Reference 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.




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


    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 Reference Terms of Use. Reference How this information was developed to help you make better health decisions.


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