Prevent Kids' Food Allergies, Start Peanuts, Eggs Sooner

Amid rising rates of children’s food allergies, surprising new guidelines call for introducing babies at ages 4 to 6 months to the most allergenic foods—as a strategy to prevent food allergies.

New scientific data suggests that early introduction of highly allergenic foods—such as milk, eggs, peanuts, soy, and shellfish—may reduce children’s risk for developing food allergies, according to new recommendations from the American Academy of Allergy, Asthma & Immunology (AAAAI), published in Journal of Allergy and Clinical Immunology: In Practice.

The recommendations are a dramatic reversal of American Academy of Pediatrics (AAP) guidelines issued in 2000, which advise delaying milk until high-risk kids reach age 1; eggs until age 2; and peanuts, shellfish, tree nuts, and fish to age 3.

The AAP defined high-risk kids as those with one or more close relatives (a parent or sibling) who had an allergic condition—an extremely broad definition, given that about one in five Americans suffer from some form of allergy, according to the Asthma and Allergy Foundation of America.

In 2008, the AAP released revised guidelines, stating that there was little evidence that delaying allergenic foods prevents food allergies. However, the AAP didn’t offer any specific guidance on when to introduce these foods, leaving parents confused about the best way to protect kids.

Up to 6 million American kids have food allergies—and the rate has jumped by nearly 20 percent since 1997, for as yet unknown reasons. About 90 percent of food allergies are triggered by just eight foods: milk, soy, wheat, peanuts, tree nuts, shellfish, eggs, and fish.

New Tactics to Prevent Food Allergies

To identify evidence-based prevention tactics, the AAAAI combed through medical literature and issued the following recommendations:

   ·        Exclusive breastfeeding for at least 4 and up to 6 months is advised. For bottle-fed babies, hydrolyzed formula—which contains protein that has been broken down (hydrolyzed) to be more easily digestible—may have benefits over those that contain cow’s milk during the first 4-to-6 months. Brands of hydrolyzed formula include Alimentum, Nutramigen, and Pregestimil. The researchers found no evidence that soy formula reduces food allergy risk.

    ·         Pregnant and breastfeeding women don’t need to eat a special diet to protect babies from food allergies. In fact, “avoidance diets,” in which pregnant or breastfeeding women shun highly allergenic foods, are notrecommended by the AAAAI. However, the group says that more research is needed to tell if avoiding peanuts during pregnancy or breastfeeding plays any role in reducing peanut allergy in kids, since studies done to date had contradictory results.

   ·      Parents can introduce foods—including highly allergenic ones—once babies are 4 to 6 months old. The AAAAI advises trying a few typical baby foods, such as cereal, fruit, or vegetables, and once those are well tolerated, introduce potentially allergenic foods.

How Solid is the Science Supporting the New Guidelines?

“There's been more studies that find that if you introduce [highly allergenic foods] early it may actually prevent food allergy," David Fleischer, MD, coauthor of the medical journal article and a pediatric allergist at National Jewish Health in Denver, told the Wall Street Journal.

"We need to get the message out now to pediatricians, primary-care physicians and specialists that these allergenic foods can be introduced early,” added Dr. Fleischer.

Among the research cited in the report are these studies:

A small study found that delaying introduction of wheat until a baby reaches 6 months did not protect against wheat allergy. Another study found a significantly higher rate of wheat allergy in 5-year-old kids whose parents had delayed giving them wheat until after age 6 months. Therefore, no data supports holding off on giving babies wheat.

·         Small amounts of cow’s milk, such as that in baked goods, and dairy products like yogurt and cheese are safe to introduce before age one. One study found that early exposure (before a baby reached 14 days of age) as a supplement to breastfeeding may protect against milk allergy.

·         Several studies show that if kids start eating cooked eggs when they are 4 to 6 months old, they are less likely to develop egg allergy, while babies who aren’t introduced to egg until they are more than 10 months old have a higher rate of egg allergy at age 5.

·         One study found a ten times higher rate of peanut allergy in Jewish kids in the United Kingdom, where parents usually avoid feeding babies peanut butter, than in Jewish kids in Israel, where peanut butter is eaten in higher amounts at a younger age. However, parents should consult an allergist before feeding a baby peanut butter if other family members are allergic. Whole peanuts are a choking hazard and shouldn’t be given to kids under age 5.

What’s the Theory Behind Exposing Babies to Allergens?

One theory holds that if kids aren’t exposed to substances in highly allergenic foods early enough, their body is more likely to view them as foreign invaders and attack, leading to an allergy.

"The body has to be trained in the first year of life," says Katie Allen, a professor and allergist at the Murdoch Childrens Research Institute at Royal Children's Hospital in Australia, according to the Wall Street Journal.

“We think there's a critical window, probably around 4 to 6 months, when the child first starts to eat solids," she says.

Another explanation for the rise in allergies and autoimmune disorders is the “hygiene hypothesis,” the theory that we’ve become so clean that the immune system isn’t adequately challenged by germs during childhood, making it more prone to overreacting to harmless substances, such as proteins in certain foods.

By Lisa Collier