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Friday, July 1, 2011

Yo-yo dieting not so bad


Okay, don’t get me wrong.  Maintaining a healthy weight throughout one’s lifetime is obviously the ideal.  However, many people who try to lose weight end up regaining much or all of that weight back.  This cycling between low and high weights has been dubbed ‘yo-yo dieting’ and has been assumed to have detrimental health consequences, so much so that some people advocate remaining obese rather than yo-yoing.  Not so, according to Edward List of Ohio University, who presented a paper on the topic at the 93rd Annual Meeting of The Endocrine Society. 

List divided 30 mice into three groups, one fed a high fat diet, one a low fat diet, and the third cycled between four weeks of high fat feed and four weeks of low fat feed.  The mice were allowed to live out their normal lifespans.  I guess if you’re a lab mouse, this is the gig to get. 

Along the way, the mice were measured for weight, body fat and blood glucose levels. Although the yo-yoing mice had large fluctuations in health measures (depending on where they were in their cycles) overall, they had better outcomes than the high fat mice.  Not only were their lifetime average metabolic numbers better, but they lived almost 35% longer.  In fact, mice on the yo-yo diet lived as long as the low fat mice.

To be clear, this was only a small mouse study.  Still, the results do suggest that people who are trying to lose weight should not give up if they fail a few times and regain that weight.  Cycling through weight gains and losses may not be hurting them as much as not even trying to lose weight.