Need at least 3 days to start AUTOPHAGY, so if you go 4-5 days once a month, you’ll repair dysfunctional cells, including immune cells. Must drink salt water along the fast, salt to taste, as you are constantly peeing out salt. Black coffee, water, salt water, non sweetened tea are okay. Anything that spikes insulin such as carbs or proteins will immediately kick you out of autophagy.