The food you consume during the eight hours, how you choose to consume it, and how much you choose to consume greatly affect the effectiveness of your fasts. Fasting for 16 hours doesn't grant you permission to binge for the remaining eight.
Fasting works primarily by creating a caloric deficit. If you fast for 16 hours and then overcompensate the remaining eight, you're negating one of the primary benefits of fasting. So take our simple advice on what you can eat: Eat normally during your eight-hour window; in other words, eat only as much as you need to feel satisfied and not a smidgen more.
When eating, make sure you focus on quality over quantity. The quality of the food you put in your body is just as important as how much you consume. Furthermore, quantity dictates your weight, whereas the food quality impacts your overall health.
For what you eat, try the Paleo Diet, which simplifies making good food choices, because it focuses on eating foods that have the highest nutrient-to-calorie ratio, and eliminates all processed junk foods.
In addition, here a few more quick rules for eating during the eight-hour window:
Make your first meal your biggest meal. Coming off your fast, ensure that your first meal is your biggest meal, especially if you just worked out. Fasting increases assimilative capacity, or how much food your body can process efficiently at one time.
So yes, you can get away with eating a slightly larger meal than usual coming off a fast and not have to worry about storing excess body fat, as long as you don't completely overdo it.
Eat until you're satisfied, not stuffed. A popular publication recently wrote an article on micro-fasting that misled people into thinking that they could eat whatever they wanted, as long as they kept their eating within an eight-hour window. This article was wrong. If something sounds too good to be true, it probably is.
You want to eat sensibly throughout the eight hours, which means you eat healthful foods and only as much as you need to feel satisfied, not full, stuffed, or bloated.
Fill up on protein and veggies first. Make your calories count, so fill up on the good stuff first — the stuff that has the highest nutrient-to-calorie ratio. In almost all cases, that stuff includes protein sources, such as fish, meat, and poultry, and fibrous vegetables, such as broccoli, kale, and cauliflower. From there you can move onto more complex carbohydrates, such as fruits and/or sweet potatoes.
Eat when you're hungry and don't eat when you're not hungry. The eight-hour eating window doesn't mean that you should spend the entire eight hours eating. You want to eat when you're hungry and not eat when you're not hungry with a strong emphasis on the latter.
Space your meals out as much as possible to prevent overeating and to not overtax the digestive system. For example, having two meals four hours apart or something close to that is better than having one meal every hour.
The same foods you shouldn't eat when intermittent fasting also apply to micro-fasting.