![](https://www.fastday.com/wp-content/uploads/2017/07/800-calorie-fasting-1-350x233.jpg)
Is is true the 5:2 diet now allows 800 calories on a fast day?
In recent months it has been reported that Dr Michael Mosley, author of the original The Fast Diet book, has ‘relaxed the rules of 5:2’ by increasing the fast day calorie allowance to 800 calories.