Obesity epidemic in America found significantly worse than previously believed

The scope of the obesity epidemic in the United States has been greatly underestimated, according to a study published Apr. 2 in the open access journal PLoS ONE. Researchers found that the Body Mass Index (BMI) substantially under-diagnoses obesity when compared to the Dual Energy X-ray Absorptiometry (DXA) scan, a direct simultaneous measure of body fat, muscle mass, and bone density.

The disparity is particularly significant for women of advancing age, those with high blood leptin levels, and the normal weight obese.

The study found that as many as 39 percent of Americans who are classified as overweight based on BMI are actually obese as measured by DXA.

"The BMI is an insensitive measure of obesity, prone to under-diagnosis," said Eric Braverman, M.D., one of the authors of the study, "while direct fat measurements are superior because they show distribution of body fat."

Co-authors Braverman and Nirav Shah, M.D., M.P.H., recognize the convenience, safety, and low cost of the BMI, yet agree that it is an outdated mathematical equation that needs to evolve in order to correctly evaluate body fat.

"These estimates are fundamental to U.S. policy addressing the epidemic of obesity and are central to designing interventions aimed at curbing its growth," the authors say, "yet the [current policies] may be flawed because they are based on the BMI."

The authors also found that levels of leptin, a hormone protein, are strongly correlated to body fat. They suggest that, in the absence of DXA, leptin levels may be used in conjunction with BMI to provide a more accurate measure of adiposity, and provide a leptin-adjusted BMI table to do so. They also note that the American Society of Bariatric Physicians use both BMI and DXA as criteria for interventions, which "may be a reasonable transition in ."

add to favorites email to friend print save as pdf

Related Stories

Growth hormone increases bone formation in obese women

Nov 29, 2011

In a new study presented today at the annual meeting of the Radiological Society of North America (RSNA), growth hormone replacement for six months was found to increase bone formation in abdominally obese women.

Recommended for you

Pregnant woman taken off life support in Ireland

Dec 26, 2014

A brain-dead pregnant woman was taken off life support Friday after a court ruled that her 18-week-old fetus was doomed to die—a case that exposed fear and confusion among doctors over how to apply Ireland's ...

'Tis the season to overeat

Dec 25, 2014

(HealthDay)—Overeating is common during the holidays, but there are strategies that can help you eat in moderation, an expert says.

Don't let burns mar your holidays

Dec 25, 2014

(HealthDay)—The risk of burns from fires and cooking accidents increases during the holidays, so you need to be extra cautious, an expert says.

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.