From, “Why we get fat“, the fantastic follow-up to “Good calories, Bad calories” by Gary Taubes:
In other words, the science itself makes clear that hormones, enzymes and growth factors regulate our fat tissue, just as they do everything else in the human body, and that we do not get fat because we overeat; we get fat because the carbohydrates in our diet make us fat. The science tells us that obesity is ultimately the result of a hormonal imbalance, not a caloric one—specifically, the stimulation of insulin secretion caused by eating easily digestible, carbohydrate-rich foods: refined carbohydrates, including flour and cereal grains, starchy vegetables such as potatoes, and sugars, like sucrose (table sugar) and high-fructose corn syrup. These carbohydrates literally make us fat, and by driving us to accumulate fat, they make us hungrier and they make us sedentary.
If your goal in reading this book is simply to be told the answer to the question, “What do I do to remain lean, or lose the excess fat I have?” then this is it: stay away from carbohydrate-rich foods, and the sweeter the food or easier it is to consume and digest—liquid carbohydrates like beer, fruit juices and sodas are probably the worst—the more likely it is to make you fat, and the more you should avoid it.