To Lose Weight, Add Fiber

A study has found a form of “permissive” dieting—focusing on what you can eat, not on what you can’t—produced almost as much weight loss as more restricted dieting. Published in the Annals of Internal Medicine, the study divided 240 adults with metabolic syndrome into two groups. One group simply focused on consuming 30 grams of fiber per day, while the other group followed the more complex American Heart Association (AHA) diet, which emphasizes fiber, vegetables, legumes, lean proteins, and whole grains, and minimizes sugar, sodium, alcohol, and saturated fats, among other things. After participants had been on the two diets for 12 months, here’s what the researchers discovered:

  • Those following the high-fiber diet lost an average of about 4.5 lbs, while those on the AHA diet lost just slightly more—almost 6 lbs.
  • Twelve participants dropped out from the high-fiber group, whereas fifteen dropped out of the AHA group.
  • However, seven participants developed diabetes in the high-fiber group, but only one did in the AHA group.

This study indicates both the potential and limitations of permissive dieting. On the one hand, participants focusing on just a single dietary component—fiber—lost a notable amount of weight and may have found the diet easier to follow (based on the drop-out numbers). But on the other hand, the multi-component AHA diet may be more effective at helping prevent the development of diabetes, and did result in more overall weight loss.

Source: Annals of Internal Medicine

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