I used the 5-2 fasting diet for a year last year before falling off the wagon. Bought MMs books and they were my health bibles. After coming off 5-2 I have gained a stone in weight so have taken an interest again only to find out there is a revision. On my fast days I was consuming 500 calories or less but now the rule seems to be 800 calories. I understood the scientific facts said that 500 calories for a woman was the maximum amount of calorific intake for a fast day to reset blood sugars and tackle visceral fat.