I can't find anything to specifically address this, but this board has taught me that much of what I have believed about nutrition is not true. I'll admit that I've been going pretty hard at this and I've lost 3-4 pounds a week (so far, it's early - I know that can't keep up) by having three or four days a week where I'm eating under 800 - sometimes under 500 - calories a day. I think I probably wasn't over 800 calories most of this last week, except maybe Saturday. I didn't plan it at first and I'm not really "counting calories' but it's been easy because I'm just not very hungry. Now, is this considered "Intermittent Fasting" or is it more than that? Am I likely to start losing muscle tone or developing any heart problems are whatever that go along with "crash dieting"? I honestly don't know how long I want to keep it up for, but the quick initial results are a very big boost to my confidence and committment.