If you look up the Horizon programmes on BBC website, you can access the blurb about this programme. Down one side there is a list of blogs all about the 5/2 system, they are really enlightening and you can also see just how confused people are about how it all works. We recorded the original programme and have watched it twice, just to make sure we have the gist of it. You can "fast" on two days, not necessarily consecutive ones, taking in 400 - 500 calories for women, 600 calories for men. I thought you had to take them in all in one go and then not eat anything else for 24 hours, but it seems that you can divide the calories as you want - the presenter had a breakfast and then dinner each evening, confining his intake to 600 calories each day.
Today, a very wet and gloomy bank holiday, we decided in our wisdom (?) to start on day one. Had all our calories for breakfast, and now hubbie talking about just a little piece of cheese and crackers. Looking over I see he has gone to sleep, so perhaps he can last a bit longer! Can't get out to garden, very difficult to distract ourselves from our usual routine of three meals a day plus mid-morning and mid-pm snacks, too muddy for walking out, but we shall get through. We are more interested in this method for its health properties, as DH is on statins for high cholesterol and my levels are going up, too, so anything to help. It does help to concentrate the mind on calorie content, too, not a bad thing - I think we will try to eat less on the days off, too.
Good luck everyone! 