Diet soda is not, it turns out, a panacea for overeating. But it’s not just because ordering a burger, fries, and a diet soda means you’re still consuming too many calories; it’s because diet soda itself may increase your waistline.

The news comes from a University of Texas study that examined data from 474 participants in the San Antonio Longitudinal

Study of Aging, a continuing study of elderly Mexican and European Americans. The result: Diet soda drinkers saw a 70% increase in waist circumference compared with non-drinkers over the course of a decade. People who drank more than two diet sodas a day saw a staggering 500% greater waist circumference compared to non-drinkers.

Part of the problem may be traced back to aspartame, the artificial sweetener used in many diet sodas. According to a study from other researchers at the university, heavy exposure to aspartame may directly increase blood glucose levels, leading to an increase in diabetes risk. “Artificial sweeteners could have the effect of triggering appetite but

unlike regular sugars they don’t deliver something that will squelch the

appetite,” explained Sharon Fowler, an obesity researcher who co-authored both studies, in an interview with the Daily Mail. (If this sounds familiar, here’s why.)

So what’s the solution? Cut down on your soda intake–both diet and regular. And while you’re at it, stop driving so much and exercise more at your job. Or get your employer to join Keas, where you’ll get rewards, instead of just being scolded.

[Image by Flickr user “Cowboy” Ben Alman]

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