Body mass index (BMI), the standard measure of obesity, has been deemed badly flawed, say US physicians following results of a data analysis recently published in The Lancet. Researchers from the Mayo Clinic College of Medicine in Minnesota have found that patients with higher BMI—considered overweight—had better survival rates than patients with low or normal BMI. Their study data came from 40 studies covering 250,000 people with heart disease. Lead researcher Francisco Lopez-Jiminez is quick to point out that their study results do not suggest that overweight people are healthier, but rather, the BMI as a measurement is no longer effective. "Our data suggest that alternative methods might be needed to better characterize individuals who truly have excess body fat, compared with those in whom BMI is raised because of preserved muscle mass." A separate study involving 52 countries compared 4 different body measures: BMI, waist-to-hip ratio, waist measure, and hip measure. Results showed waist-to-hip ratio to be the surest predictor of heart attack risk."

Ms. Farley is a freelance medical writer based in Wakefield, RI.