I didn't mention it before, because I'm not sure how much it helped, but I too had food allergy testing, and also cleaned up my diet.
I had an ELISA IGG food allergy
test, and tested positive (off the scale) for milk
and egg, so I haven't eaten any for a few years. After I made the switch, my digestion improved and my breathing passages opened up noticeably, but I still have the brain fog.