On the Thin Zone Keto other hand, when you give your body more energy (calories) than it needs, leptin levels are boosted, which can then have positive effects on fat oxidation, thyroid activity, mood, and even testosterone levels. So if it's an increase in leptin levels that you really want, how do you best achieve it? Eating carbohydrates is the most effective way. Second to that is eating protein (high-protein meals also raise your metabolic rate). Dietary fats aren't very effective at increasing leptin levels, and alcohol actually inhibits it.