By Claire Bates and Tom Leonard PUBLISHED: 05:39 EST, 4 April 2012 | UPDATED: 20:03 EST, 4 April 2012 Overweight or obese? BMI underestimates how fat a person is in nearly half of cases The obesity epidemic could be far worse than previously realised because of serious flaws in the  way body fat is measured, according to a study. Researchers said the Body Mass Index – the formula usually used to determine fat – drastically underestimated how many people should regard themselves as unhealthily overweight or obese. More than a third of adults in the  U.S. are considered obese.
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Combining BMI with blood test to measure levels of key protein would be 'more accurate'
'These estimates are fundamental to @placeholder policy addressing the epidemic of obesity and are central to designing interventions aimed at curbing its growth,' the authors said, 'yet the [current policies] may be flawed because they are based on the BMI.'