Over the past five or six days of this protocol, you’ve been in deep ketosis and burning only fat, but you haven’t had to be particularly calorie restricted. In order to reset leptin levels and prevent a large drop in energy levels, you need to re-feed. Contrary to our normal recommendations, you need to pound down the carbs. When it comes to normalizing leptin levels, fat has no effect, while carbs are going to send them sky high.
Tight deadlines, bills, your kids—whatever your source of stress, having too much of it may make it harder for you to drop unwanted pounds, especially from your middle. And it's not just because you tend to reach for high-fat, high-calorie fare when you're stressed, though that's part of it. It's also due to the stress hormone cortisol, which may increase the amount of fat your body clings to and enlarge your fat cells. Higher levels of cortisol have been linked to more visceral fat.
This may explain why the fat-burning effects of eating more protein were confirmed in a study published in the American Journal of Physiology. One group was fed a high-protein diet (just over 1 gram per pound of body weight per day) while the second group consumed an amount closer to the lower recommendation of the RDA (recommended dietary allowance). The group eating the higher-protein diet burned the most fat.