A lot of children under the age of 3 experience food allergies. This is more common in families with a history of allergies, food or otherwise. Exposing babies to high allergen foods at a young age also increases their chances of developing food allergies. Ninety percent of these food allergies are to one of the following 5 foods: soy, peanuts, cow’s milk, wheat or eggs.

While it is possible to have several food allergies at once, the majority of children who develop a food allergy only experience it with one food. A reasonable percentage of children allergic to cow’s milk also experience food allergies with soy products.

Severe food allergies cause instantaneous inflammation of the lips, tongue or throat; itching; or tingling when the child has minimal contact with the food. The worst allergies can cause anaphylactic shock and sometimes death. Nuts and fish are usually the culprits of these life-threatening allergies.

In general, though, typical food allergies don’t produce such extreme symptoms. Gastrointestinal disruption is common, causing diarrhea, excess gas, nausea or even vomiting. Newborns may experience mucous or bloody streaks in their stool. But it isn’t always loose stool; food allergies can occasionally trigger constipation.

Other common symptoms include wheezing, hives, a stuffy or runny nose, ear infections, asthma, colic and eczema. These last two symptoms, characterized by irritability, may be the only symptom of a food allergy. If your baby has this sign, try eliminating high allergen foods and see if the symptom disappears.

Allergies to food are usually not contagious, and most babies will outgrow any developed food allergies by the time they turn 3 years old. (Allergies to nuts and fish are the exceptions.) If the allergy continues, helping your child avoid the offending food for a year or two will likely cause the allergy to disappear.