> It's what and how much you eat that matters. It's only how much you eat. Conservation of energy still applies, and 3500 kcal are still a pound of fat. It d

> It's what and how much you eat that matters. It's only how much you eat. Conservation of energy still applies, and 3500 kcal are still a pound of fat. It doesn't matter where the calories come from, they always end up either burned or as fat. The "how much" is regulated by negative feedback. Whenever you eat sugar, insulin is secreted, which ends the craving. Whenever you eat fat or protein, leptin is secreted, which causes a feeling of satiation. Leptin is secreted by fatty tissue, so the fatter you are, the earlier you are satiated. As a result, everyone has an equilibrium weight at which he will eat exactly enough to replace the expended energy. But that's not what's happening right now. We tend to constantly gain weight. Slowly, but without an apparent limit or any kind of feedback. That's where the "what you eat" comes in. Something is fouling up the feedback mechanism. Maybe something that causes the release of neither insulin nor leptin. Something we now consume in bulk, but didn't use to. Maybe we shouldn't do that.