" Hormones modify this flow of fatty acids back and forth across the membranes of the fat cells, and they modify the expenditure of energy by the tissues and organs. Hormones, and particularly insulin—“even in trace amounts,” as Ernst Wertheimer explained—“have powerful direct effect on adipose tissue. "

― Gary Taubes , Good Calories, Bad Calories: Challenging the Conventional Wisdom on Diet, Weight Control, and Disease