Burns fat: You can drop a lot of weight — and quickly — on the keto diet.[3] Ketones suppress ghrelin — your hunger hormone — and increase cholecystokinin (CCK), which makes you feel full.[4] Reduced appetite means it’s easier to go for longer periods without eating, which encourages your body to dip into its fat stores for energy. Learn more here about the keto diet and weight loss. 
The keto diet did jump considerably in one specific category, however: This year it tied with several other diets for No. 2 in Best Fast Weight-Loss Diets (after the HMR Diet, a commercial plan that replaces most meals with pre-packaged nutrition bars and shakes), up from No. 13 last year. “Yes, you can do this for quick weight loss,” says Dr. Katz, “but I wouldn’t recommend it.”
On a ketogenic diet, your entire body switches its fuel supply to run mostly on fat, burning fat 24-7. When insulin levels become very low, fat burning can increase dramatically. It becomes easier to access your fat stores to burn them off. This is great if you’re trying to lose weight, but there are also other less obvious benefits, such as less hunger and a steady supply of energy. This may help keep you alert and focused.
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