One reason for the failure of low fat diets is that they may increase Physiological adaptations that increase hunger, slow metabolism and prevent ongoing weight loss. However, low fat diets were never intended to increase consumption of simple carbs, but rather fruits/vegetables and whole grains. The low carb diet may attenuate these adaptations and reduce insulin secretion. Whether over-use of this diet will also result in an absence of continued benefit may also occur. Trial and error continues in the field and is part of the scientific process and the prevention of harm needs to be considered as we go forth answering important questions about dieting and the prevention of cardiometabolic symptoms associated with disease.
Ludwig DS, Lowering the bar on the low-fat diet. JAMA, publish online Sept, 2016.