Hi ...Last week I genuinely made a mistake and ate the wrong piece of toast. I only realised when I realised it tasted too nice. Nothing happened. Emboldened by this I had another piece yesterday. This evening I paid for it by having explosive diarrhoea (sorry) and a cracking headache.
I have not touched gluten for 18 months (Gluten intolerant)
What made the first piece of toast ok and the second so painful ?