If you have a child with food allergies, you probably have a lot of questions, like whether your child will outgrow the allergy. The answer, it seems, depends on the child and the nature of his allergy. While some food allergies do lessen or disappear with age, others continue for a lifetime. Allergy doctors aren't entirely sure why one child outgrows a food allergy and another does not, but there are some theories. Here's what you need to know about childhood food allergies:

What causes a food allergy?

Food allergies occur when your child's body mistakes the food for a harmful substance. Under normal circumstances, your child's body attacks foreign bodies, like viruses, to prevent him from getting sick. In the case of a food allergy, your child's defense system releases immunoglobulin E (IgE) to fight off the imagined danger from a specific food. This may cause your child to experience a variety of symptoms from sneezing and watery eyes to hives, skin rashes and trouble breathing. In extreme cases, your child may experience anaphylaxis, a condition where the mouth and throat swell and restrict breathing.

What some common allergies in children?

Although doctors don't know why some foods set off an allergic reaction, there are some common offenders. These include milk, eggs, soy, nuts—especially peanuts—and shellfish. A child may be allergic to one or more food.

Do children really outgrow food allergies?

Recent studies conducted by the American College of Allergy, Asthma, and Immunology (ACAAI) and a 2013 study published in the Annals of Allergy, Asthma and Clinical Immunology confirm that many children do outgrow allergies. According to the ACAAI study, the likelihood of outgrowing a food allergy depends on the child and several identified factors:

• Children who develop food allergies early in life are more likely to outgrow them.
• Children with multiple food allergies are less likely to outgrow them.
• 55% of children with egg allergies outgrow them by the age of 6 or 7.
• 45% of children with milk allergies outgrow them by age 6 or 7.
• Only 16% of those with peanut allergies and 13% of those with shellfish allergies outgrow them.
• Those who outgrow peanut allergies typically do so by age 10, while those who outgrow shellfish allergies do so by age 12.
• Some children do not outgrow allergies until the age of 16.

Is the food allergy gone for good?

Typically outgrowing a food allergy means the symptoms are gone forever, but that isn't always the case. People can, and do, develop new allergies or experience the re-occurrence of allergic symptoms at any time during their lifetime. Reoccurring food allergies typically occur when the child has not been exposed to the food for a long time.

Can you cure food allergies?

According to an article by Sherry Coleman Collins, MS, RD, LD, in Today's Dietitian there are two new techniques currently being practiced in the United States for building a tolerance of foods that cause and allergic reaction.

1. Avoiding the offending food and then gradually reintroducing it into the child's diet, under the supervision of an allergist, may help build a tolerance for the food. This may be done by introducing small amounts of the food in baked goods or other dishes.
2. Sublingual immunotherapy may also be effective in building a tolerance. This consists of placing a small amount of the food under the tongue. Sublingual immunotherapy should be done by a allergy doctor or other medical professional, as it requires monitoring for adverse reactions.

What about allergy shots?

Allergy shots also introduce a small amount of the substance your child is allergic to. These shots are given over a period of 1 to 5 years to build up an immunity to the offending substance. Many children no longer show symptoms of an allergic reaction to the food when they stop taking the shots, but it is not foolproof. Allergy shots do not bring about immunity is some children.

If your child shows symptoms of an allergy that does not go away, he may be allergic to a specific food. Your doctor or allergist can test him to determine the cause of his allergies.