metabolism and food

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There's One Diet Factor That Makes a Difference

The tweak that can help keep your metabolism humming along: getting enough protein. "It seems to have an effect on the number of calories the body burns," says Hall. "It's not huge, but it's measurable. Plus, we know that protein helps you feel fuller longer, so you eat less overall." (Most experts recommend eating between .8 grams and 1 gram of protein for every 2.2 pounds that you weigh.) Here's what doesn't have an effect: Low-carb diets, often touted as a way to boost metabolism. Hall and his colleagues just published a study showing that at best, super-low-carb diets (with carbs totaling about 5 percent of total calories) might help you burn about 60 calories more per day and, at worst, moderately-low-carb diets (roughly 30 percent of total calories) actually slow your metabolism by about 100 calories per day. You might think, hey, 60 calories is still something, but keep in mind that very-low-carb diets are hard to maintain, so you likely wouldn't get the effect for long. (This study was conducted in men, but previous research by Hall that included men and women showed similar results.)
The Takeaway: If you really want to maximize your metabolism, focus on getting adequate protein. If you want to go reasonably low-carb for other health reasons, that's fine—just don't expect your body to burn extra calories because of it.