There are many tried and true operating levers in the world: mechanisms, tactics and proven best practices that work. If you want to lose weight, avoid triggering an anxiety attack, lower your risk of Alzheimer’s and diabetes, then don’t eat sugar. Simple. One small input leads to a large output. Replacing carbs with cardio, meditating and journalling, regular hand washing, adequate sleep, some yoga–and yes hydration–are a personal operating system of best practices. Pull the levers and get the benefits, almost guaranteed. But most people don’t pull the levers available to them. Evidently workable operating levers are not enough.