22 July 2009 10:00 AM
Jeremy Singer Vine:
For years, critics of the body mass index have griped that it fails to distinguish between lean and fatty mass. (Muscular people are often misclassifed as overweight or obese.) The measure is mum, too, about the distribution of body fat, which makes a big difference when it comes to health risks. And the BMI cutoffs for "underweight," "normal," "overweight," and "obese" have an undeserved air of mathematical authority. So how did we end up with such a lousy statistic?The answer is here.