I used to have recurring ear infections until I gave up milk and ice cream. I still eat cheese. I went to several doctors, including an allergist, was put on antibiotics, then cortisone, then finally found out by accident that eliminating milk cleared up my sinuses! Then I read Dr. Mercola's "Don't Drink Your Milk" article and was shocked. No doctor ever suggested I might be sensitive to the swill that passes for milk these days.
I also avoid cold food in general, especially iced drinks and fruit juice. A lot of fruit juices make me stuffier, especially orange juice.
Not only does it help my sinuses, it improves my mood!