I feel great during a week long fast. Seems pretty simple, when I'm in pain, or healing too slow, a quick fast helps a ton.And I can ''cheat'' whenever I want to, unlike a diet. Interval fasting works for me as well, one meal on the evening.
I haven't gone carb free, nor see the need. Just reduced carbs, drastically.
If ''cheating'' restarts your weight loss, you weren't eating enough calories.
Low calorie diets tell your body that there is food, but sparingly amounts of it, time to store that energy and fatten up.
Fasting tells your body that there is no food. Time to burn energy to go elsewhere, release some adrenaline to hunt better.