Long Water Fasts are for Healing...a physical problem, or Obesity. They are not to be done continuously, and only take a short time when compared to non-fasting. Too many long Fasts during a short period of time can be dangerous.
What one needs to be concerned with is eating (or non-fasting) as a way to Heal or lose weight. The best plan there being undereating on highly nutritious foods.....WY