Body Mass Index: a big fat lie

''First, it fails to provide an accurate measure of overweight and obesity. Second, it is arbitrary in its classifications of normal, overweight and obese. Third, its classifications of overweight and obese generally do not correspond to increased risk for premature death or serious illness.

And fourth, its unscientific character has allowed it to be transformed into the major tool for misrepresenting the risks of overweight and obesity and justifying a ‘war on fat’.
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The studies by Flegal (at the US Center for Disease Control) and Gronniger have found that the lowest death rates are for those in the overweight category of BMI 25-25.9. Indeed, this group was most likely to live the longest. Gronniger’s study reported that moderately obese men had the same mortality rate as ‘normal’ weight men.'' [source]