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The Basics of Food Allergies

As you may know, our immune system protects us from infections by attacking the viruses and bacteria that can make us sick.

With a food allergy, the body's immune system mistakenly sees certain food proteins as unwelcome intruders (allergens) and attacks them. This attack is called an allergic reaction. The eight most common food allergens are the proteins found in milk, eggs, fish, shellfish, tree nuts (e.g. almonds, walnuts), peanuts, wheat and soy. However, it is not uncommon for children to be allergic to other foods or have multiple food allergies. Infants and young children are more sensitive to these proteins and are more prone to food allergies in general. Your child may be allergic to one or more food proteins and may even be allergic to small fragments of these proteins found in hypoallergenic hydrolyzed formulas.

Some allergic reactions are immediate and severe, while others are less severe and may take days to appear. For example, severe breathing problems could appear instantly after eating just half a peanut. Or the reaction may take days and a larger portion of food—such as a glass of milk—to appear. Skin rashes and diarrhea are typical of these kinds of allergic reactions.

Most of these symptoms can also be caused by conditions other than a food allergy, but it’s better to be safe than sorry. If you suspect your child has a food allergy, ask your doctor.