Fasting requires you to abstain from calorie-dense foods, until the eating window.
Truth is, most 0-calorie foods for fasting aren’t absolutely zero calories, but they are so low in calories they may be consumed during a fast, depending on your specific fasting regimen.
Sadly, there are no true 0-calorie foods. Some beverages contain a negligible number of calories and can be consumed during almost any fast.
0-calorie foods for fasting are available on a unique fasting schedule called dirty fasting. Dirty fasting is a form of time-restricted eating
The National Institute on Aging reviewed multiple studies to establish whether or not intermittent fasting has health benefits for humans
First, fasting triggers a metabolic switch, where your liver turns fat into ketones for energy, instead of using glucose.
Results are limited because human trials have mostly been conducted on overweight, middle-aged adults, and the long-term effects of intermittent fasting have not been well studied in humans