My boyfriend has been having constant health issues for approximately 6 or 7 months now, he has been constantly fatigued, nauseous, irritable, he has headaches all the time, he has sinus problems, a sore throat, and he is always coughing up phlegm. He has been to many doctors and done countless tests, all of them saying nothing is wrong with him. We finally decided to explore the possibility it might be a food allergy, and tried eliminating milk products from our diet. For a while it seemed to get better, but he is starting to feel rotten again. Could this be some other type of food allergy?