Liquid Fasting

Fasting has its pros and cons, and I'm personally not a fan of it. But if you're going to do it, I'd absolutely have protein shakes. Make them with fruit so you get at least some nutrients, and take a multi-vitamin. Don't do it for more than one day, and certainly don't do it often. Just my opinion, I really don't know a ton about fasting.

I've recently read several posts on intermittent fasting and I'm considering doing it once a week, but I can't just go on water alone! What if I were to do a day of just protein shakes AND water?

I incorporate fast days into my program. I generally use protein shakes. Other times, I'll do juice fasting. Make sure you are getting nutrient rich protein shakes.

Brian, I do it as a part of my calorie cycling. I only do it a few days a month. One shake day every 7-10 days or so. Just to shake the body up. My shakes are about 200 calories each and I drink 4 or 5 of them. It's no different than when we weren't watching calories and we had really busy days where we barely got a chance to eat. Before calorie counting, have you ever had a day where you ate a little something for breakfast, then got so busy that you skipped lunch and then finally ate something for dinner? On that day, you most likely took in less than 1000 calories. It didn't kill you. It's the same thing. Just planned with nutrition in mind.

For juice fasting, check out the movie "Fat, Sick, and Nearly Dead." It's available free on Hulu.com or or Netflix. When planned and thought out, reasonable fasting has benefits and will not harm you.