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Home > Fitness & Health > Health Library > Body Mass Index (BMI)
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.
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
Very high risk
Obesity III (extreme)
40 or above
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.
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.
Current as of:
December 11, 2019
Author: Healthwise StaffMedical Review: E. Gregory Thompson MD - Internal MedicineKathleen Romito MD - Family MedicineMartin J. Gabica MD - Family MedicineRhonda O'Brien MS, RD, CDE - Certified Diabetes Educator
Current as of: December 11, 2019
Author: Healthwise Staff
Medical Review:E. Gregory Thompson MD - Internal Medicine & Kathleen Romito MD - Family Medicine & Martin J. Gabica MD - Family Medicine & Rhonda O'Brien MS, RD, CDE - Certified Diabetes Educator
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