I mean, I know it's got something to do with 'food optimising' and that there are red and green days, but I have also read about unlimited foods such as potatoes etc, and I just don't get it... 
I don't want to join something that's not for me, so can someone give me a rough run down of what it all means and how you use it please? eg what are 'red' and 'green' days? Can you have a red day one day and green the next, or do you have to stick with one or the other?
Thanks