If you’re a parent to a baby that's a few months old, you probably have questions about the best way to introduce solid foods to your child – and if there is a connection to food allergies. With the rise of food allergies, answers to these questions are important.

Kids With Food Allergies (KFA) asked two allergists on our Medical Scientific Council common questions parents have about preventing food allergies and introducing foods. Here’s what allergists Michael Pistiner, MD, MMSc, and David Stukus, MD, had to say.

Question: How do I know if my child is at high risk for food allergies?

Dr. Stukus: There are many factors that have been associated with children who develop food allergies, but the strongest risk factor is whether that infant has developed moderate-to-severe persistent eczema.

Eczema is a chronic skin condition that often presents in the first few months of life and causes dry skin, as well as red, irritated, inflamed patches. It often affects the skin inside the elbows, behind the knees, on the torso, or face. Infants with truly persistent or severe eczema often go on to develop allergies and asthma as they get older.

Targeting early allergen introduction toward this group of infants will likely have the most benefit. This is different than babies who have cradle cap that improves with age or a few mild eczema patches that pop up every so often or improve with moisturizers. Older siblings with food allergy and parental history of allergies or asthma are often considered risk factors, but these aren’t as strongly connected as the eczema risk.

It’s also important to note that some children develop food allergies and don’t have any risk factors at all, but these are the minority. Lastly, individual food allergies are not inherited. There is no gene for peanut allergy. But the predisposition to develop allergies in general is often inherited.

Question: When and how should I introduce solid foods to my child, especially the most common allergens, like egg, milk, peanuts, wheat, soy, sesame, and tree nuts?

Dr. Pistiner: In general, the time to introduce solids is when your baby shows interest. They’ll need to have head control and be able to accept food without thrusting it out with their tongue. Starting with an infant cereal or a pureed fruit or vegetable may be what your primary care doctor recommends. Interestingly, if your child is at risk of developing allergies then considering solid introduction from 4 to 6 months of life will be a good target.

Dr. Stukus: Common food allergens should be introduced beginning around 4 to 6 months of age once babies are showing an interest and ability to swallow pureed and solid foods.

There are a wide variety of foods that contain these allergens that families can offer. Infants should not replace breast milk or formula with drinking cow’s milk until 12 months of age due to risk for anemia. Otherwise, they can try yogurt, cheese, or other forms of dairy.

The key is for parents to actively introduce these various foods AND then keep them in their diet consistently. This is very different than offering a few small bites and not trying again for several months.

Question: What can I do to prevent my child from getting food allergies?

Dr. Stukus: Unfortunately, there is no 100% proven method to prevent food allergies. And there is no single cause as to why some children develop food allergies and other children do not.

But the best path toward preventing food allergies from developing in your child is to have them start eating allergenic foods – such as cow’s milk, egg, wheat, soy, peanut, tree nuts, and seafood – beginning around 4 to 6 months old and then keeping these foods in their diet consistently. This strategy helps their immune system develop a tolerance toward allergenic foods.

It is also helpful to offer your baby a wide variety of foods as diet diversity has been associated with fewer food allergies. The beauty of this approach is that there is no special medicine or supplement involved. It’s based simply on feeding a nutritious diet rich with a variety of foods while parents bond with their infant as they learn to eat.

Question: How do I know if my child is having a food allergy reaction when I start introducing solid foods?

Dr. Pistiner: Signs of an allergic reaction in a baby can vary from child to child.

They can include a rash or hives (red, raised rash/welts) on the skin. The rash or hives can be where the food touches, or in areas where it didn’t also. You can see swelling, including swelling of the face, lips, or tongue. It can cause itching in a baby and you may see them rub, scratch, lick, or mouth objects, depending on where the baby feels itchy.

Reactions can also cause vomiting and diarrhea.

Some symptoms that can be clues of a more severe reaction include:

• Coughing, wheezing (high pitched noise with breathing), trouble breathing that can look like pulling in between the ribs, flaring of the nostrils
• Change in skin color (blue, grey, mottled, pale) especially of and around the lips
• Sudden behavioral change in the baby, including limpness or floppiness, lethargy (difficulty waking up), and unable to stop crying even though all other things that may cause crying have been taken care of
  
  

Question: Should I avoid eating certain foods while pregnant or breastfeeding to prevent food allergies? Or is there a certain type of formula I should give them?

Dr. Stukus: This is a very important question for mothers everywhere as they are often riddled with guilt over these choices or when their child develops food allergies. The good news is that maternal diet during pregnancy or breastfeeding does not cause or prevent food allergies. Mothers should eat whatever they want, guilt free! Evidence also does not support using hypoallergenic formulas for the purpose of preventing food allergies.

Question: Years ago, doctors recommended keeping certain foods out of your child’s diet until they are 1 year old to prevent food allergies. Why did that guidance change?

Dr. Stukus: While flip-flopping guidance may seem frustrating for some, this is actually a really good thing. This means that evidence has changed and, more importantly, the experts who formulate the guidelines recognize this shift and need to support a new approach.

In 2000, the American Academy of Pediatrics specifically recommended avoiding highly allergenic foods until after 1 year of age because this is what the expert opinion and prevailing understanding reflected at the time. Just eight years later, the recommendations were changed to remove the avoidance portion but still didn’t actively recommend feeding allergenic foods to infants.

Then, in 2016, the landmark LEAP trial demonstrated for the first time that early introduction of peanuts to a group of infants with eczema and/or egg allergy between 4 to 11 months of age AND ongoing inclusion in their diet at least three times a week until 5 years of age showed a dramatic reduction in peanut allergy compared with infants who avoided peanut. Other observational and randomized controlled trials have since demonstrated similar benefits for early and ongoing introduction, especially for egg and peanut.

Given this new evidence and understanding of the immune system, as well as significant benefit compared with risk, the recommendations were changed again in recent years to now actively recommend early introduction. When done properly, science should be objective and everchanging. That is how we progress and remain as up to date as possible.

Question: I heard you should give peanut to your baby to try to prevent them from getting a peanut allergy. How do I do that and when?

Dr. Stukus: Yes, current recommendations suggest actively introducing age-appropriate forms of peanut to infants beginning around 4 to 6 months of age AND keeping it in their diet on a consistent basis, ideally at least three times a week.

Nothing we do in medicine is 100% effective, but early introduction is the best path toward preventing peanut allergy from developing. Every baby is different in regard to their readiness for solid foods, and some may not be ready until after 6 months, which is OK as well.

Parents can use peanut butter thinned with water, peanut flour or powder, or peanut puffs. Whole or partial peanuts are a choking hazard and should never be given to children until they are at least 4 or 5 years old. The goal is to give at least two (2) grams of peanut protein each time.

Download, print, and share KFA’s Resource:
Preventing Peanut Allergy: Introduce Peanut Foods Early to Your Baby

The National Institutes of Health also provides excellent instructions for free.

Question: If my child has allergic proctocolitis, how and when should I introduce solid foods?

Dr. Pistiner: Allergic proctocolitis is a non-IgE-mediated food allergy that can cause visible blood in the baby’s stool. This is for the most part outgrown relatively quickly but sometimes can cause delays in the introduction of foods other than the proctocolitis trigger. Babies with proctocolitis triggered by cow’s milk may have a higher chance of also having soy-triggered proctocolitis. Seek guidance from your health care team for managing these and a plan for attempting reintroduction. The introduction of foods like egg, peanut, sesame, wheat, fish, and shellfish should not be delayed.

Question: My older child has food allergies. How can I introduce foods to my baby while preventing food allergy reactions in my older child?

Dr. Stukus: This is a common question and really should involve a discussion with your personal allergist as there are many factors to consider, including:

• Age of the sibling
• What foods they are allergic to
• Their personal risk for reaction from various types of exposures
• Family dynamics

In general, the risk for an allergic reaction from casual exposure to a food being in the home, or even someone else eating during the same meal, is very low. The focus should be on preventing accidental ingestion for the older sibling while also avoiding unnecessary precautions that can be burdensome.

Question: Should I give my child with a food allergy a little bit of the food they are allergic to every day to help them outgrow it?

Dr. Stukus: Absolutely not! The standard of care for food allergy management is avoidance of allergens as any ingestion may cause an allergic reaction to occur. Oral immunotherapy is a highly structured and supervised process that is used in some circumstances as a way to help lower the risk of severe allergic reaction from ingestion of small amounts. But oral immunotherapy should only be done under the close supervision of a board-certified allergist and after families have a full understanding of the risks, benefits, and expected outcomes of treatment. This is a daily treatment that requires close monitoring for allergic reactions, consistency, and structure.

Michael Pistiner, MD, MMSc, is Director of Food Allergy Advocacy, Education and Prevention for the MassGeneral Hospital for Children, Food Allergy Center.

Dr. Pistiner has special interests in food allergy and anaphylaxis education and advocacy, infant food allergy management, health care provider education, facilitating collaborations between the medical home and school health, and maintaining quality of life in children with food allergies and their families.

David Stukus, MD, is a Professor of Clinical Pediatrics in the Division of Allergy and Immunology, Director of the Food Allergy Treatment Center, and Associate Director of the Pediatric Allergy and Immunology Fellowship Program at Nationwide Children’s Hospital and The Ohio State University College of Medicine. He is board certified in allergy/immunology and pediatrics.

Dr. Stukus has devoted his career to communicating evidence-based medicine and best clinical practice to colleagues, medical professionals of all backgrounds, patients, and the general public. In addition to providing clinical care for children with all types of allergic conditions, he participates in clinical research, quality improvement, patient advocacy, and medical education.

Medical Review: May 2022 by Michael Pistiner, MD, MMSc, and David Stukus MD