Arthur De Vany's Evolutionary Fitness Art's Blog on Fitness, Health, Aging, Nutrition and Exercise

In my book, I argue that leptin was used to signal "not empty" with regard to fuel supplies. It loses its signal when the tank is full and when there is glucose aplenty in the blood supply, which is why insulin screens out the leptin signal. I think this went unnoticed by readers. People seem to think that it focuses almost entirely on insulin. A nice discussion of the inceasing understanding of leptin is in the following. It completely supports the view I take in the book. Leptin's multi-system effects also fit the "expendable system" view I argue for; when you are starving, only the truly essential systems get resources. Reproduction and immunity crash. They are systems to move the genes into the future or to maintain. When there is no tommorrow, they must be sacrificed.