Fasting is fine if done for therapuetic purposes. The person fasting should read all they can about the fasting process because there is a right way and wrong way. It can be very weakening if done the wrong way.
Many people fast 1-3 times a year and have no eating disorder. They do it for health or spiritual reasons. It is good to fast if done properly with frash juiced vegetables and fruits slowly sipped thru=out the day so blood Sugar remains steady. Also I belive ome fiber to keep the bowel moving is recommened. Some people may take off from work during that time to rest, while others have plenty of energy.
Fasting with diet soda and gum is not appropriate and can destroy vital organsand the brain.