Are fasting diets good to cut calories?
Fasting will cause you to fixate on food, which may have the opposite effect than you intend. You'll be much hungrier and overeat once you're "allowed" to eat again. It will also counteract what you did the day before.
Additionally, by being gluttonous one day and malnourished the next day. You may feel sick by going from an empty stomach to a full stomach. The only thing a fasting diet will do is get you nowhere fast. Your body needs nutrients from food, and there are so many other healthier and less drastic ways to lose weight.