Almost all processed foods contain yellow food dye. Many contain red food dye. These are known to cause allergy reactions. They are not used to help you but to make products look prettier so that you buy them while in the store. Often these food dyes are the cause of cerebral allergy and allergy induced headaches.
Stress can bring on an allergy attack.
Stress can cause you to deplete the vitamins and minerals in your body. Taking vitamin supplements will improve your tolerance of many allergens. Your body requires vitamin C to process many other vitamins, vitamin C can be very helpful in reducing allergic reactions, and vitamin C is very safe. See related article Allergy Relief with Vitamin C . Multiple-vitamin tablets are the best choice.