We know sleep, exercise and diet are vital for health. But why?

The benefits of all three come down to a crucial piece of cellular kit Sleep. Exercise. Eat well. It’s the oldest recommendation in medicine, repeated so often it’s become a cliche. We know the advice, even if we don’t always follow it. But have you ever stopped to wonder why these three seemingly different habits have such remarkably similar effects on our brains and bodies? For generations we’ve…