Mouse Study: Yo-Yo Dieting Beats Not Dieting at All

Mice fed an alternating high-fat and low-fat diet lived almost as long as mice on a constant low-fat diet--and longer than mice on a constant high-fat diet. Katherine Harmon reports

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Sticking with a diet can be tough. Which is why so many people end up on the dreaded yo-yo track, dieting for awhile, gaining weight when they stop, then dieting again.

Yo-yo dieting has been thought to be unhealthy. But a new study with mice suggests it’s not so bad—and that it could make for a much longer life than never cutting calories at all.

The research looked at mice that always got a healthful, low-fat diet, those that only ate high-fat food, and others that spent their whole lives switching between low-fat food one month and high-fat food the next.

The yo-yoers lived almost as long as the mice given a consistently low-fat diet. That’s not saying that the yo-yoing mice were healthy. During their high-fat periods, they were overweight and diabetic. The new research was presented earlier this week at the annual meeting of the Endocrine Society.

The researchers say people shouldn’t accept yo-yo dieting as the norm. But the findings should encourage overweight people to try dieting even if they’re concerned that they won’t stick with it. And people who've lost weight and gained it back shouldn’t be afraid to give it another try.

—Katherine Harmon

[The above text is an exact transcript of this podcast.]

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