Anyone do this? 600 calories one day, around 3000 the next, I did the 600 calories yesterday and it was actually quite easy; even though i was a bit hungry i had a surprising amount of energy. Today I have eaten quite a lot and still feel quite good. I will keep this up and see how it goes. Just to clarify, I'm doing this for health, digestion, energy and skin reasons NOT for weight loss
This study is fascinating
http://www.bbc.co.uk/news/health-19112549 (linked from this which discusses ADF)
I'd rather be the monkey on the right!