Cottage cheese also works for me. I don’t know why. I figure it’s the protein but I don’t know, yet Milk is something I don’t drink because it bothers me [except Lactaid]. I don’t know what works for most people honestly. In your situation, I’d go with the recommendations but also experiment as well. Notice how you react to different foods and drinks. Taking notes about yourself as you eat (something like a “reaction journal” is probably the strongest step you can take along with gathering whatever outside education you can find.
A “how I react” journal could be like an “anti-shopping list”.