Funny you should say that... I've noticed it too... and now, everytime I eat bread I'm absolutely bloated! I'm the only person I know that doesn't or very rarely eat sandwhiches!
Gotta say you aren't alone in this. For the last 18 months I have found that too much white bread, whole grain cereals and most meat (I only really eat chicken and bacon now) bloat me up terrible and everyone else usually suffers for it later on.......
I too have had an odd gastric proplem the last few months - thought it was the tablets I`m taking. I do make a sandwich each lunchtime but never considered it a cause. Sometime in 2006, I am sure that I read about a government bid to have some chemical added to flour before making bread - had forgotten all about it till reading your thread. Anyone else recollect it?