Measuring Obesity: A New, Maybe Better Alternative to BMIS

For years, obesity has been measured by BMI — Body Mass Index. The CDC calls BMI a "fairly reliable indicator of body fatness for most people." But critics call the BMI badly flawed, and in 2007, Kate Harding put together a slideshow demonstrating how problematic the BMI can be: A 5 foot tall size 4 woman is considered overweight; the average top fashion model's BMI is 16.3, though a BMI of 18.5 or below is considered underweight; someone considered "morbidly obese" is not 400 lbs, but 280 lbs.

But researchers at The City College of New York have come up with a new obesity measurement tool called A Body Shape Index (ABSI); it combines BMI and waist circumference. ABC News reports:

The researchers measured ABSI in more than 14,100 American adults who participated in the National Health and Nutrition Examination Survey (NHANES) between 1999 and 2004. They found that a high ABSI, indicative of a large amount of belly fat, significantly increased the risk of premature death. A high BMI also predicted the risk of an early death, but to a lesser degree than ABSI.

Nir Krakauer, a co-author on the study, says: "High ABSI may identify people who have unhealthy body shapes despite having weight and waist circumference within the normal range, and such people may benefit from diet and lifestyle changes."

One thing unclear about ABSI is whether it takes natural, inherited body shapes into account. Two women of the same height and weight could have vastly different ABSIs if one is pear-shaped and the other is apple-shaped. Or if one has an hour-glass waist and the other has a straight, ruler or tube shaped body.

Still, in terms of mortality risks, experts believe that abdominal fat is a big one; it's been linked to lots of health problems. And a new piece in The Lancet claims that physical inactivity is just as dangerous as smoking and obesity. Add that to stress, high blood pressure, phthalates, dairy, sitting down, sugar, climate change and, well, everything, you're basically about to die any minute now. Just something to think about as you ponder your navel — as in, how far it is from your body, thus raising your ABSI.

ABSI, New Obesity Measure: Better Than BMI? [ABC News]
Physical inactivity causes 1 in 10 deaths worldwide, study says [CNN]

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