I highly doubt it's diet related. I eat pretty well to begin with. I just live in a place that has extremely high grass pollen. And after living here for 30 years, my body was like, fuck you, you have allergies now. 

 I personally lived through it and can attest to it. You are under no obligation to heed my advice, but might be worth just trying out and seeing how it goes. 

 I honestly don't know what I would change in my Diet. My avoid vegetable oils, I eat a pretty balanced diet of meats and veggies and i shop, as local as possible.