We are all different, with different diets, eating habits, living in different environments, etc. can affect that answer you are looking for.
I have lived on fruits and vegetables all my life, but some fasts were harder than others.
I would say try one month of eating organic raw plant based foods and see how you feel, walk daily for 20 minutes, then do a kidney, colon and liver cleanse and see how you feel, then fast. Lengthy plan? Sure.
Most people are looking to get quick results and rushing in to fasting to get the gains and then go back to the old ways of eating junk foods.