Today I have realized that all the foods that's making me nauseous are very "sticky", and all the foods I can tolerate are are not sticky at all.
There is very clear correlation between the food's "stickyness" and my digestive issues after eating it.
Even different forms of the same food can make night and day difference - I can tolerate wheat pasta (which is not very sticky), but I can't tolerate pure wheat porridge (which is very sticky). Drinking water after something like thick wheat porridge is absolute disaster for my digestion.
The same goes for rice - I can't handle regular rice, but the "glass" rice noodles are fine.
It seems it is more the form and mechanical properities of the food that is triggering my nausea, not the food itself.
This is my experience as well! The stickier the food the worse. For me cooked oatmeal is disaster as it turns into a sort of heavy paste. But Steam rolled oats "raw/uncooked" with milk is no problem at all. Same goes for rye bread. If I cook it into sludge it just sits in the stomach and causes pain/nausea. Wheat pasta is really safe for me as well - dont even feel it digesting.