YouTube excerpt (Gary Brecka) explaining how the hormones leptin and ghrelin regulate appetite, energy expenditure, and fat storage, and how calorie restriction and intermittent fasting alter these hormones—potentially making sustained weight loss harder by increasing hunger and reducing satiety signals.
Two hormones that control your appetite and your energy balance. Let's talk about leptin and ghrelin. These work in opposition to each other, creating an interconnected dynamic for managing food and energy storage. Leptin originates from your fat cells. As your fat stores grow larger, leptin levels rise, sending signals to your brain to suppress your appetite and elevate your energy expenditure. Ghrelin, produced mainly in your stomach, does the opposite. It stimulates hunger and it promotes fat storage, especially when your stomach is empty. When you consume less calories, ghrelin levels increase while leptin levels decrease. While that might sound good to not be eating a lot, many people don't know that eating less can actually create challenges for weight management. Your body interprets calorie restriction as starvation and responds by ramping up hunger signals while reducing the I'm full signal. While intermittent fasting and doing the occasional water fast has its place in protecting your health and metabolism, living in a constant calorie restriction may be messing with your hormone balance.
