How It Works

The short fasts affect your body on a molecular level, decreasing insulin levels, aiding in cellular repair, increasing HGH (Human Growth Hormone), which aids in fat burning and muscle-building, and inspiring your bod to tap into stored fat, rather than carbs, to burn energy. Courtney Peterson, Ph.D., an assistant professor in the department of nutrition sciences at the University of Alabama at Birmingham, told Women's Health, "Studies suggest you keep more muscle and lose more fat than on other diets, even if you lose the same number of pounds." And all you have to do is keep an eye on the clock!

[Photo via @sweatsandthecity]

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