Myth 1: Fasting will make you lose muscle mass.

This is false on many levels. Your body burns more fat than muscle when in a caloric deficit. If you consume plenty of protein and lift heavy weights on non-fasting days, your body will primarily burn fat and preserve your hard-earned muscle during fasting.

Myth 2: Religious fasting is the same as fasting for health.

Not at all. If fasting is part of your religion, that's fine, but that's not what this is about. I fast for health purposes, which looks slightly different from religious fasts. The main difference is that I still drink water during my fasts, and you can also consume vitamins and pharmaceutical drugs if they have no calories.

Myth 3: You need to start and stop your fast at a specific time.

You don't. It can be from 7 PM to 7 PM the next day, or 6 AM to 6 AM the next day. The timing is flexible. You fast because you want to improve the way you look and feel, not because you need to.

Myth 4: Your body will go into starvation mode if you fast.

Starvation mode, or adaptive thermogenesis, only kicks in if you've been eating way below your usual amount for months on end.

When you're in a constant caloric deficit for a prolonged period, your metabolism slows down because your body is trying to conserve energy, believing you're starving. Fasting once every two weeks won't trigger starvation mode. To be safe, I recommend slightly overeating once a week.

Myth 5: Eating 500 calories a day will make you less hungry than fasting the entire day.

This might seem counterintuitive, but whenever you consume anything, your digestive system starts working, and your hunger hormone kicks in. Even if you eat just a little, you'll likely feel hungrier than if you hadn't eaten anything at all.

If you avoid consuming any calories for about 20 minutes, your stomach will stop growling, and you'll no longer feel hungry. In fact, you'll feel fuller by doing nothing than if you had a snack 30 minutes earlier.