Fasting

I have a friend, he often fasting for health. After he explained to me the benefits of fasting, I understand. According to him, when we fast, our tool digestion are given the opportunity to rest.
With the rest of his digestion, the body will remove the poison, sewage and waste, that accumulate in the colon. In addition, because the digestion in this situation rest, the cells in the body's organs will update itself.
He also said, resistance to its body becomes stronger.
I've never tried fasting. But, I ever try to eat fruit and vegetables in just one day. Its results, the next day my guts out like cleanse, I feel relieved. I think is like doing colon cleanse. I have become light. Finally, I tried for two days. After two days my body weight down two kilogram. A health professional ever said that this is a way for detoxification.