From all sorts of things I've read over the years, I think diarrhoea is due to detox brought on by the calorie restricted fasting. I'm pretty sure 500 cals in a day is low enough to stir up toxins, done regularly.
I just did a google search, something may contain relevant information on one of these pages. I will get some time tonight to read through a few pages.
https://www.google.com.au/search?client=safari&rls=en&q=5:2+and+diarrhoea&ie=UTF-8&oe=UTF-8&gfe_rd=cr&ei=is6fU8SoJ-XC8gf-h4CgCQ
chinchin
I just did a google search, something may contain relevant information on one of these pages. I will get some time tonight to read through a few pages.
https://www.google.com.au/search?client=safari&rls=en&q=5:2+and+diarrhoea&ie=UTF-8&oe=UTF-8&gfe_rd=cr&ei=is6fU8SoJ-XC8gf-h4CgCQ
chinchin