In previous posts I have highlighted how fasting turns on autophagy:
Autophagy as I said before:
.......... (literally self-eating) a process in which your cells consume and recycle damaged internal material.
The process seems to be triggered when the energy content of the cell declines so that the cell literally consumes itself. It goes after the damaged materials first, so there is a strong link between repair of damaged tissues and fasting or low energy state in the cell. So, it you are over-fed you down regulate cellular repair. You want to go hungy episodically to turn on cellular autophagy and repair those damaged tissues.
Stuart has highlighted another immunological process phagocytosis that is limited by eating simple carbs (sugar) but promoted by fasting!
Thanks for pointing that out Stuart