Another study, published in the New England Journal of Medicine in 2008, assigned 322 moderately obese adults to one of three diets: calorie-restricted low-fat; calorie-restricted Mediterranean; and non-calorie-restricted low-carb. After two years, the Mediterranean group had lost an average of 9 7/10 pounds; the low-fat group, 6 4/10 pounds; and the low-carb group, 10 3/10 pounds. Although weight loss didn't differ greatly between the low-carb and Mediterranean groups, both lost appreciably more than the low-fat group did.
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.