Diabetic man’s waistline better indicator than BMI

Researchers have found that a man’s waistline is a better warning sign of his risk for type 2 diabetes than his body mass index.

Researchers at Johns Hopkins University tracked 27,270 men over a period of 13 years and found that men who had larger waists or higher overall body fat had a greater risk of developing type 2 diabetes. Of the men studied, 884 had diabetes.

However, they said, the correlation between waistline measurement and actual diabetes risk was closer than the link between BMI and the disease.

BMI doesn’t directly measure fat, but is a formula that considers weight and height. Obesity experts say the index is useful but shouldn’t be used without taking into account other factors.

The waist-hip ratio compares waist measurements with the measurement of the hip, defined as the largest circumference between the waist and the thighs.

Alan Cherrington, president of the American Diabetes Association, said the results support previous research that has found waistline fat “is worse for you than other kinds of fat.”

Researchers believe fat cells in that area may affect the liver differently, or there are signaling molecules in that type of fat cell that may affect diabetes, said Cherrington, who is also the chairman of the Department of Molecular Physiology and Biophysics at Vanderbilt University.

Cherrington said the results appear to show your waistline is a better predictor of diabetes risk and “if you combine BMI and waist circumference, you’re getting the best of both worlds.”

They found better correlation between waist size and cholesterol, blood pressure and blood glucose levels than BMI in both men and women, including blacks, Hispanics and whites, largely independent of age.

“Both BMI and waist circumference are useful tools to assess health risk,” said the study’s lead author, Youfa Wang, “but abdominal fat measured by waist circumference can indicate a strong risk for diabetes whether or not a man is considered overweight or obese according to his BMI.”

The Johns Hopkins University was the first research university in the United States. It was founded in 1876.

Investigators found that those with waists larger than 34 inches were twice as likely to have diabetes compared to men with the smallest waist circumferences, 29 to 34 inches.

Those with waists over 40 inches were 12 times more likely to have the condition, the researchers reported in the March issue of the American Journal of Clinical Nutrition.

So, in addition to measuring BMI, the researchers recommend that doctors measure waist size as an indicator of central obesity to estimate diabetes risk for patients and make decisions with them about changes in diet and lifestyle.