Bloating with gas, bloating without gas?

[SamYo123]

How is it possible to bloat, and get no gas on 1 food (milk) but, get gas and no bloat from oat bran?

 

[Phosphor]

I can't answer that but if it were me....I would not eat either of those, because of the consequences. There is a wonderful test out there called the MRT that will return what foods are inflammatory (pain-causing, plus other results) and it is not an allergy test. Nor, of course, is it covered by insurance, because it actually gives valuable information.
I would also find and do a microbiome test to see what you're missing as well as what is there that may not be good. I cannot digest dairy, and I also cannot have the type of gluten that is in oats, so I myself avoid both of those.