Q&A: Food additive intolerance 1) What is food additive intolerance and can you tell us what the most common symptoms are? Food additive intolerance is a non-IgE mediated food hypersensitivity. The hypersensitivity is induced by the food additives via a direct mast cell activation. Although the exact pathophysiology is unknown, various clinical signs are characteristic of food additive intolerance. These include cutaneous symtoms like redness of the skin, urticaria and angioedema as well as other organ related symptoms, such as dyspnea, hypotension or dizziness.