Taubes’ alternative hypothesis runs something like this: Americans (and everyone else) are eating more because they’re hungrier, and they’re hungrier because of the hormone insulin. Insulin is secreted into the blood by the pancreas, and removes sugar from blood and allows it to enter cells as fuel. If you eat carbs, your blood sugar starts to rise, but insulin brings it back down to normal. When insulin is high, like after a meal, it reduces appetite and turns sugar into fat for storage. When insulin’s low, like when you haven’t eaten in a while, you start burning fat instead.
