I had a friend who was only able to do it for 5 days. He discovered the morning of day 3 that he was no longer wheezing from his asthma in the mornings. Something he has been dealing with for months! He was amazed and felt great. What the fast did to him was make him realize that some of his wheezing symptoms were probably food related so he's slowly working a variety of foods back into a healthier diet. Here we are four weeks later and he's following a mostly vegetarian diet and feeling great. In that sense, for him some fasting had major benefits and is helping him adhere to a more healthy diet.