cheelu, I'm embarking on the 5/2 diet, 5 days of eating normally and 2 days of 500 calories, today is a 500 calorie day and so far I'm getting through it with loads of green tea, but time will tell how successful it's going to be for me. The 2 hard days should not be consecutive. I'm taking a long term approach and am not looking for a rapid weight loss but one I can sustain. The two people I know who have done it for a while said it has made them feel a lot better and have more energy as well as reaching their desired weight, and more energy is something else I would like as well as weight loss. Like most I have piled on more than I would like to have done over the last decade, I used to be 8 stone before I had my children and stayed around 9 stone for a long time whilst they were growing up. I was diagnosed with an under active thyroid in my mid 40s and take 100 mcg of thyroxine for this, which I thought would help me loose loads of weight when I first started taking it,but it hasn't! I tried the no carbs diet a while back, can't remember what it's called now, although I lost weight rapidly, it gives you real meat eating dinosaur breath and leaves you very constipated and for me it made me crave things I wouldn't normally want to eat like fruit cake and frankly after a while you'd kill for a banana! It wasn't for me. I know you have kicked off with this post cheelu, but I would be interested to know if there are any GNs out there on the 5/2 diet, and if so, how are you finding it?