Andreas Birkenfeld is searching for the key to a longer life. His theory goes: if your metabolism drops, your body ages more slowly, you stay slim and are less susceptible to disease. He's already proven it with mice by lowering their metabolism artificially through genetic modification. Now Birkenfeld wants to find out if the same can be applied to humans. And he wants it in pill form - one tablet for a healthy life right up to the ripe old age of 120.