Gung gung (maternal grandpa) says the reason the prophets in the bible lived so long is that their diet was all-natural, so gung gung avoids eating processed sugar. Every morning he has a bowl of oatmeal that he microwaves with water and dried fruit that he cuts up himself with a scissor. I haven't gone quite as far, but I've started using dried fruit and honey instead of sugar. I don't know how long the prophets lived, but Gung gung's made it to 83 so far.