"A ‘low fat diet’ — even one restricted in calories — is high in carbohydrate, which drives up insulin levels. Insulin is a hormone that drives fat into storage (i.e., into fat cells) and stimulates hunger. A low carbohydrates diet, on the other hand, allows insulin levels to remain low and fat stores to be burned in the context of reduced hunger and cravings."
Jeff S. Volek and Stephen D. Phinney