People with food allergies have an allergic reaction when they come in contact with certain foods. This happens because their immune system overreacts to the proteins in that food. Twelve million people in the United States have food allergies. The most common offending foods are cow’s milk, eggs, peanuts, wheat, soy, fish, shellfish, and tree nuts.
Signs of a food allergy include rash or red, itchy skin, stuffy or itchy nose, sneezing, or itchy and teary eyes, swelling, vomiting, stomach cramps or diarrhea. In extreme cases, people can have a serious reaction called anaphylaxis, which is a medical emergency.