Preventing food allergy in children

Is your child at risk of developing a food allergy? What can you do about it? About 6 percent of children under age 5 have a food allergy. Food allergy symptoms often begin before the age of 2 — after a child's first exposure to the allergy-triggering food. Experts are researching whether the sequence and timing of the introduction of foods might play a role in preventing allergies in children. But there's already some evidence that taking certain steps may help prevent food allergies if your child is at risk.

What is a food allergy?

A food allergy is caused when a specific protein in a food triggers an immune system response in the body. After the initial exposure, the body remains sensitive to that protein — and has allergic symptoms whenever a food containing that protein is eaten.

Food allergy symptoms in children can range from mild to severe. They can include red, itchy skin and gastrointestinal problems including vomiting, diarrhea, colic and constipation. Less commonly, allergies can trigger gastroesophageal reflux disease (GERD). In severe cases, an allergic reaction can lead to anaphylaxis, which constricts the airways and requires emergency medical attention.

What foods cause allergies?

Children are often allergic to cow's milk, wheat and soy. The good news is that children often outgrow allergies to these foods. Some children develop allergies to tree nuts, fish or seafood, which are more likely to last into adulthood. Less often, other foods cause allergies.

Can food allergies be prevented?

Although there is no surefire way to prevent your child from developing a food allergy, introducing foods at the right age may help. Experts still need to do more studies to find out exactly what works best, but here are some steps you can take:

• Avoid peanuts during pregnancy and while nursing. Eating peanuts during pregnancy and while breast feeding may increase your child's risk for developing a peanut allergy and other allergies — especially if you have a family history of allergies.
• Give your child only breast milk for the first 6 months, if possible. This is the best source of nutrition for your infant — and it may help prevent your child from developing food allergies that can last well into childhood or even adulthood.
• Wait until your child is 6 months old to introduce solid foods. Especially if you have a family history of food allergies, taking steps to prevent early exposure to foods that can cause allergies is a good idea. As a child grows older and the digestive system matures, the body is less likely to absorb food or food components that trigger allergies. Experts believe that waiting to introduce solid foods until your child is 6 months old may help prevent allergies to those foods.
• Introduce cow's milk after one year. Studies show that waiting to introduce cow's milk until your child reaches age 1 reduces the chance your child will develop a milk allergy.
• Introduce eggs at age 2. This may help prevent your child from developing an egg allergy.
• Introduce nuts and seafood at age 3. This may help prevent your child from developing an allergy to these foods. (Do not give your child whole nuts until he or she has molars and can chew them well.)
• Introduce all new foods gradually and one at a time. Before introducing mixed foods that could cause an allergic reaction, introduce each new food on its own. Don't mix foods until you're sure each individual food is tolerated.
• Give your child cooked or homogenized foods. Many foods are less likely to cause an allergic reaction after they are cooked. (However, be careful. A few foods — such as cod and celery — still contain allergy-causing proteins after cooking.)

Are some children at higher risk for food allergies?

If you have a food allergy, your child is more likely to develop one too. Having asthma also increases your child's risk of developing a food allergy. If you have a food allergy or asthma, you can take steps that may help prevent your child from developing a food allergy.

• Breastfeed for the first year of life or longer, if possible. Continue breast feeding after introducing supplemental foods at 6 months of age.
• Ask your doctor about using a hypoallergenic formula. Infant formulas can contain foods that cause allergies. Hypoallergenic infant formulas can be more costly — but may be less likely to trigger an allergic reaction.
• While nursing, eliminate peanuts and tree nuts (such as almonds and walnuts) from your diet. Experts think it might help to eliminate eggs, cow's milk and fish as well. If you do eliminate foods from your diet while breast feeding, be sure you are getting adequate nutrition from other sources. Your doctor may also recommend taking supplemental calcium and vitamins.

Work with your doctor to determine the best dietary plan.

While these steps may help prevent allergies, they are not a guarantee. More research on allergy prevention is needed to develop definitive guidelines about what works best. And, each child is different — so the best approach is work with your doctor or a pediatric dietician to come up with the best dietary plan for your child.