It has been known for some time that decreasing caloric intake has beneficial effects, in terms of longevity. It also has been shown that this effect exists for all mammals that were tested. So, the likely conclusion from these studies is that, for a human being, decreasing caloric intake to its subsistence level will increase the lifespan. What is interesting to me is, that the ketogenic diet causes body to "simulates" semi-starvation states, the state found during decreased caloric intake (which is likely to foster longevity). Could it be possible that the ketotic states are actually healthful, and help you live _longer_?