How It Works

The goal is to put your body into a metabolic state of ketosis, during which you rev up your natural fat-burning and additionally, produce ketones in the liver which are used to send energy to your brain. It also lowers blood sugar and insulin levels. In one study, people on the keto diet lost 2.2 times more weight than dieters on a low-calorie, low-fat plan. And though the first week is tough (many people experience a "keto flu" due to the lack of carbs), it's mostly delicious, smooth sailing after that.

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