Waist Circumference

Total body fat is not the only indicator of weight-related health problems. The way that fat is distributed also plays an important role. For example, body fat that accumulates around the waist known as abdominal fat (an "apple shape") poses a greater health risk than fat carried in the hips and thighs (a "pear" shape).

Men are genetically predisposed to gain weight around their waist, although there are exceptions. By contrast, women's bodies tend to be more "pear shaped." Overweight men also tend to have more visceral fat, which substantially increases the risk of heart disease, metabolic syndrome and diabetes.¹

Waist Circumference: A Reliable Tool
Waist circumference has been studied extensively and is shown to be a reliable measure of abdominal fat and an independent predictor of risk. ^2,3 A high waist circumference (greater than 35 inches in women and 40 inches in men) is linked to an increased risk for type 2 diabetes, dyslipidemia, hypertension, and heart disease.^1,4

BMI and Waist Circumference
Waist circumference is particularly useful in people who are categorized as normal or overweight in terms of BMI because BMI may overestimate body fat in those with a muscular build (e.g. athletes) and underestimate body fat in those with less muscle (e.g older persons). For example, there are men with broad shoulders and lean hips who, according to the BMI formula, are overweight. These men have little abdominal fat, however, and their health risk will be low as well. On the other hand, men with a BMI in the healthy range who have a high waist circumference (>40 inches) carry greater health risks. Therefore, factoring an individual's waist circumference into the BMI equation gives a more accurate picture of health risk than BMI alone. The one exception is in individuals with a BMI of 35 or over, as waist circumference adds little predictive power of disease risk beyond that of BMI.¹

How to measure waist circumference?
To determine waist circumference, locate the upper hip bone and place a tape measure around the waist (ensuring that the tape measure is horizontal) while standing. The tape measure should be snug but should not cause compressions on the skin.

Bottom Line
Know your BMI and waist circumference numbers. If they are not in the healthy range, it's time to take action and lose weight.

view footnotes

¹ Matsuzawa Y, Shimomura I, Nakamura T, Keno Y, Tokunaga K. Pathophysiology and pathogenesis of visceral fat obesity. Diabetes Res Clin Pract. 1994 Oct;24 Suppl:S111-6. Review

² Identification, Evaluation, and Treatment of Overweight and Obesity in Adults,
NIH/NHLBI.

³ Chan DC, Watts GF, Barrett PH, Burk V. Waist Circumference, waist-to-hip ratio and body mass index as predictors of adipose tissue compartments in men. QJM. 2003 Jun;96(6):441-7.

⁴ Wang Y, Rimm EB, Stampfer MJ, Willett WC, Hu FB. Comparison of abdominal obesity and overall obesity in predicting risk of type 2 diabetes among men. Am J Clin Nutr. 2005 Mar;81(3):555-63.