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How To Prevent Food Allergies in Kids


Yale Pediatric allergy specialist describes a consult program for families with young children.

For many years, the standard advice given to all parents about food allergies was to avoid introducing peanuts to young children’s diets. Delaying peanut introduction, some experts argued, might minimize risk because older children could express a reaction to peanuts, the most common—and potentially fatal—food allergy in kids in the United States.

The recommendations for other common food allergens—dairy, eggs, nuts, and fish—were similar, especially for children considered “high risk” for allergies based on certain factors, such as having eczema (also known as atopic dermatitis), a condition that can cause patches of dry, inflamed, and itchy skin.

Much of this advice, which was based on expert opinion rather than convincing data, has since changed, starting in 2015 when the Learning Early About Peanut Allergy (LEAP) study, published in the New England Journal of Medicine, showed that the early introduction and regular feeding of peanuts could prevent the development of a peanut allergy in infants considered high risk.

As a result, the American Academy of Pediatrics (AAP) changed its recommendations, saying there is no reason for parents to delay giving their babies foods that are potential allergens, including peanut products, dairy, eggs, or fish. In 2017, guidelines from the National Institute of Allergy and Infectious Diseases went a step further, encouraging early introduction of peanuts to high-risk infants.

Many parents remain confused about the matter, especially because food allergies have become so common. The Centers for Disease Control and Prevention (CDC) estimates that food allergies affect an estimated 8% of children in the U.S. (or 1 in 13 kids), which equals about two students per classroom.

To address parents’ questions and concerns, Yale Medicine and Yale New Haven Children’s Hospital launched a Pediatric Food Allergy Prevention Program for pregnant mothers and infants up to 1 year of age. Initial consultations are done via telehealth, during which patients meet with a pediatric food allergist and a food allergy dietitian to develop an individualized plan.

“We now know there is a very good likelihood of reducing the risk of allergy if we give specific, early instructions for these foods, especially for those at high risk for a food allergy,” says Stephanie Leeds, MD, MHS, a pediatric allergy and immunology physician who specializes in food allergy and who helped develop the Pediatric Food Allergy Prevention Program. “Most often, we see families with infants between 3 and 4 months of age when they are starting to introduce foods and have questions.”

Below, Dr. Leeds talks more about the program and pediatric food allergies.

What happens in your body when you have a food allergy?

A food allergy occurs when your body’s immune system (which keeps you healthy by fighting off infections) overreacts to a food or a substance in it. The immune system identifies the food or substance as a danger and sets off a protective response, with mild to severe symptoms that may include vomiting, hives, repetitive cough, tongue swelling, and/or shortness of breath. The allergic reaction often occurs within minutes to two hours of exposure to the food allergen.

Anaphylaxis—a whole-body reaction that can impair breathing, cause a dramatic drop in blood pressure, and affect heart rate—can be fatal. This type of reaction must be treated quickly with an injection of epinephrine (often known as an EpiPen®, one of many brands), which can reverse severe symptoms immediately by reducing throat swelling to open the airways.

Food allergies are more common in children than adults, but they can appear at any age; and although rare, someone can even develop an allergy to foods they have eaten for years without any prior issues.

Any food can cause an adverse reaction, but these nine types account for about 90% of all reactions: eggs, dairy and milk, peanuts, tree nuts, fish, shellfish, wheat, soy, and sesame.

The top food allergens for infants are milk, eggs, and peanuts, adds Dr. Leeds.

What makes a child ‘high risk’ for food allergies?

Food allergies can run in families, but that doesn’t mean every child has the same allergies as their parents or siblings—or any at all.

Children who are considered at highest risk for food allergies are those with severe eczema, especially early-onset eczema—meaning it develops in the first few months of life, Dr. Leeds explains.

“With eczema, the skin is broken down, meaning the barrier is not intact. That’s why the skin gets dehydrated, red, and irritated,” Dr. Leeds says. “And because the skin is damaged, food allergens, such as those from peanuts, can easily make their way through the skin and to the immune system, potentially triggering the production of allergic antibodies responsible for an allergic response.” This, says Dr. Leeds, is how people become sensitized to an allergen. The immune system's hypersensitivity can then trigger an allergic reaction when someone eats or inhales food allergens, she adds.

What happens at a visit with the Pediatric Food Allergy Prevention Program?

When a patient comes to the Pediatric Food Allergy Prevention Program, the physician and dietitian first ask questions about medical and family history to gauge the child’s risk. The team then discusses studies supporting the early introduction of possible allergens and listens to any concerns the families may have. After the visit, families will receive more information, including instructions on how to introduce foods appropriately.

“We tailor the visit to their needs. For example, if a parent has a question about the best way to introduce a potential allergen to their child, we work with them to figure out what textures the baby accepts and offer recipe ideas,” Dr. Leeds says.

If the child then has an allergic reaction, they become a patient in Yale Medicine’s Pediatric Food Allergy Program, which offers services including oral food challenges (giving a child the food allergen in question in small amounts, under medical supervision, to diagnose or rule out a true food allergy) and oral immunotherapy (giving small, increasing amounts of the allergen and monitoring them closely with the goal of desensitizing the child to it).

Ultimately, Dr. Leeds says she hopes these prevention efforts turn the tide on the increase in pediatric food allergies. “Hopefully, in the future, tests and treatments like these won’t be needed as often,” she says.