I have been reading stuff on the internet today. Specifically to do with diarrhoea after a mini gastric bypass. It seems that lactose intolerance is a major factor. Often extra lactose is added to products with dairy ingredients to make a "better" product, and, of course, it is also added to products where you wouldn't expect there to be any lactose, so label reading is essential if you have a lactose intolerance as I have now.
The other two foods listed which may cause a problem are, first, wheat products which have gluten. The suggestion is that you go without wheat/gluten in anything at all, again checking labels, for two weeks and see how things go. Reintroduce it slowly and see what happens and whether it confirms that gluten is a problem for you.
Secondly, mayonnaise. This is horrific to me. As I now can't have dairy products, mayo is one way of me having a "sauce" which I can use with so many things: shellfish, fish, chicken, raw veggies sticks, fried potatoes, hard boiled eggs etc. etc. I can't imagine not eating mayo.
So - not a good read this morning. I think I will try to do the gluten exclusion two weeks sometime soon and see how that goes, as clearly I can't continue with this bowel hassle.
Dr Robert Rutledge has several youtube videos about the mini gastric bypass operation and living with it. It is the only bypass operation he performs and he's done thousands. On the whole they are informative and interesting.