I have been on a 5 day water fast. It was not as bad as I thought. In fact, it was't bad at all.

For 5 days, I just had water and nothing else. The 4th day was little difficult. Rest of the times, I was just doing fine.

How fasting helps?

Fasting gives body the time to clear the shit(toxins) out of body.

The liver is responsible for neutralizing free radicals and detoxify the body. When we fast, no more free radicals from our unhealthy food enter our system. Fasting reduces the burden from the liver and it can do its job well.

Not a five day fast, but you should definitely go for a regular one day fast. Make sure you don't smoke particularly during fasting.