Mark Macdonald, author of the NY Times bestseller Body Confidence, is the creator of PFC Every 3. PFC stands for the three main macronutrients - protein, fats, and carbs - and eating PFC means eating a balance of all three every three hours.
Macdonald said, "eating protein positively affects your blood sugar hormone glucagon (raises your blood sugar), eating carbs affects your blood sugar hormone insulin (lowers your blood sugar), and eating fat slows down the rate of digestion by inhibiting the release of HCL (your stomach's acid). The combination of the three nutrients in the right portion sizes and intervals keeps your blood sugar balanced."
He believes that once your blood sugar levels are balanced, your body will become a "fat-burning machine," because "eating PFC Every 3 triggers the consistent release of your stored fat." You use food to create hormonal balance in the body, and that will help you lose weight, and keep it off, without feeling starving.
Per this diet, you don't need to meticulously count calories or measure portions; just listen to your body. Eat when you're about a five on the hunger scale (not full and not famished). You'll know you've eaten the right amount at each meal or snack because your hunger level will be at a five every three hours.