Doctors regard most fasting methods as lifestyle changes – not a diet.

When you practice intermittent fasting, there are no limits as to what type of foods you can eat, and you can eat as much or as little as you need to during your eating window. (Active people usually have to eat more, and sedentary people are advised not to overeat on any fasting protocol.)

That said, most people tend to eat fewer calories while fasting as a lifestyle.