HI Mrs D. and thank you for your reply!
I've had GI biopsies and auto-antibody tests done for coeliac disease and I'm negative for it although I did have iron malabsorption requiring iv iron infusions three years ago. We never did figure out why...
I have blood tests pretty frequently actually and so I can safely say that at the moment I'm mildy neutropenic with a normal vitamin d3 (25) level and a b12 level of 240. The lab range for the b12 is 250-1000 so I'm not sure whether it's a level deserving supplementation or not... All other vitamins are normal and electrolytes are also normal (with the exception of an ever-present slightly low potassium).
I had no idea about the methionine! It sounds very interesting indeed! I will definitely look into this!
Thanks again!
Ziggy