It is interesting that there are so many posts related to fasting. I see this as a positive sign. Fasting has been used for millenia to promote good health. The other benefit is undoubtedly weight loss. If you observe the 5:2 diest discussed below you can probably eat whatever you want on the 5 days but in a way to get the full health benefits its probably better to go for the monthly 5 day fast. After 2-3 days the body readjusts to the fast and this is when the real benefits come in to play - though I do not want to discourage people from even the 5:2 fast.