Adverse reaction to food is a general term that describes any abnormal reaction to a food or food additive that is eaten, whether it is caused by allergic or non-allergic mechanisms. A few specific foods seem to cause a majority of food allergies. Some of the most common food allergens are cow’s milk, eggs, peanuts, seafood’s, wheat, and soy. Nuts and seafood’s can commonly cause anaphylaxis, a life threatening allergic reaction.