Intermittent fasting, where you eat all your food in a shorter window and fast for a certain part of the day, is gaining popularity, as many people have found success with losing weight from this diet. Certified dietitian Leslie Langevin, MS, RD, CD, of Whole Health Nutrition told POPSUGAR that intermittent fasting (IF) "gets your body out of 'storage mode' and mobilizes fat stores for energy." This means that, without having a constant food source, your body will dip into the fat it already has stored as its energy source. And this helps with weight loss. These transformation photos prove that IF really works!