ALLERGIC SINUSITIS Sinusitis causes the spaces inside your nose (sinuses) to become inflamed and swollen. This interferes with drainage and causes mucus to build up CAUSES ,RISK FACTORS AND TRIGGERS   DIET-diets low in antioxidants such as vitamin C and vitamin A, magnesium, selenium, and omega-3 polyunsaturated fats (fish oil), Vitamin D deficiency DIET -high