Paediatric Health: The Introduction of IgE Food Allergens
One of the biggest questions I’ve had from parents is “when do I introduce common allergenic foods?”
This can be worrisome for parents because of all the scary stories of anaphylactic reactions to IgE foods that they’ve heard of or maybe have even seen. But did you know that introducing common IgE allergenic foods at around 6 months of age, can actually help prevent allergies to these foods? But then you might ask, “but what if my child is at high risk of an IgE food allergy?” Well, research found that it’s even better for you to start introducing these foods at around 6 months of age!
Common IgE allergenic foods for children are peanuts, eggs, cows milk, tree nuts, fish, shellfish, wheat and soy. A recent systematic review and meta analysis found evidence that early introduction (between 4-6 months of age) of eggs decreased the likelihood of developing an egg allergy, and introducing peanuts between the age of 4-11 months decreased the likelihood of developing an allergy to peanuts. Another study, a randomized control trial, looked at high risk infants (severe eczema, egg allergy, or both). These infants were randomized into two groups, the early introduction group (between 4-11 months) and the late introduction group (5 years old). The study found an overall relative risk reduction of 80% of a peanut allergy in infants who were offered early introduction of peanuts between 4-11 months of age.
In the world of IgE food allergen research, recent studies have also been looking at vitamin D levels in infants and found that they are inversely associated with the risk of food allergy. Vitamin D is a powerful vitamin, and it has many health promoting effects for the body, including its ability to be an important immune modulator. Studies have found that infant deficiency in this vitamin can decrease immune tolerance, increase risk of gastrointestinal infection; this can negatively impact the gastrointestinal epithelial barrier and thereby decrease the effectiveness in immune cells response to food protein antigens. During these studies, they found that infants who were deficient in serum levels of vitamin D had a 3 times higher chance of an egg and peanut allergy than their vitamin D sufficient counterparts. So not only is it important to expose your little ones to food allergens within the first year of life, but it is also important to ensure your child is receiving enough pure vitamin D in their formula, or the incorporation of vitamin D drops for your child if you are breastfeeding.
Pretty great information right? But then you might ask, “now, when do I introduce these foods within the first year? Should I try right at 4 months, 5 months, 6 months?” or “What if my child is low-risk of developing an IgE food allergy?” or “Now you’re mentioning vitamin D, when do I introduce that?” Well firstly, a study actually looked into the question of when to introduce these foods for high-risk children and found no significant difference in introduction of food at 3-4 months or 6 months. So as long as you are aiming at introducing in and around these suggested months, you are helping in the prevention of IgE food allergies for your infant. For low-risk, the 6 month mark tends to be most recommended! Secondly, for vitamin D, your infant should be introduced to supplementation of this vitamin from birth. If your infant is formula fed, then vitamin D is usually included in their formula composition. However, if your child is breastfed, your physician will recommend that your infant receives a 400IU drop of vitamin D each day to obtain the necessary levels to help aid in a healthy development, and most important, prevent rickets (a weakening and softening of the bones; if there is not an adequate amount of vitamin D available, calcium and phosphorus cannot be properly absorbed from the infants breast milk or food). Research has indicated the importance of vitamin D supplementation during the first year of life, and beyond.
So you are well on your way now to understanding the why and the when, but what about the who and the how? Well, who is at high-risk? Infants considered to be at high risk are those from first degree relatives with atopy or a history themselves of atopy. Atopy is the genetic predisposition of developing certain allergic disease, such as asthma, allergic rhinitis and atopic dermatitis (eczema).
Lastly, the how. Food allergy can been driven by commensal microbiota and diet. When these two things interact, they help decide the mucosal immune tolerance of your body. The mechanism that leads to food allergies is the lack of immune tolerance, and clinical tolerance of these allergens.To elaborate, the immune system is one of the main reasons as to why there is development of a food allergy, or lack thereof. The immune system is protein specific, and has the ability to assess each food as it enters your infants body. By continuing small introductions of food allergens while your infants immune system is at its most open for learning and developing, can be one of the main preventative strategies in decreasing your infants chance in developing an intense food allergy. If you are feeding your child some of these foods and they are taking it well, then continue to offer the food 2-3 times a week to continue with tolerance building for that food.
Fun fact! If you are breastfeeding, keep it up! Breastfeeding has many positive benefits for immune system development and food tolerance for your infants, including in the support of decreasing the risk of food allergies.
Unfortunately, there are a subset of infants that will still develop an allergy to an IgE allergen, but our attempts to help decrease that chance are definitely warranted and worth a go! Some of the reactions to watch out for that may indicate your child has an IgE sensitivity or allergy are nausea, vomiting, abdominal pain, diarrhea, and an itching of the mouth or pharynx. If you’re super nervous about some allergen introductions, I have found that some parents feel much more comfortable attempting the introduction in their child’s paediatricians office! Speak to your paediatrician if you think that this is the better option, opposed to home delivery. Your healthcare providers are here for you!
Check out these resources if you are interested in learning the studies mentioned above in detail, or the complex immunobiology of IgE food allergen development.
Abrams, E., et al. (2019). Timing of introduction of allergenic solids for infants at high risk. Paediatric Child Health, 24(1): 56.
Chan, E.S., et al. (2018). Early introduction of food to prevent allergy. Asthma Clinical Immunology, 14(2): 57.
Yu, W., et al. (2016). Food allergy immune mechanisms, diagnosis and immunotherapy. Nat Rev Immunology, 16(12): 751-765.
Mutlu, G., et al. (2011). Prevention of Vitamin D deficiency in infancy: daily 400IU vitamin D is sufficent. Internationl Journal of Pediatric Endocrinology, 2011(1): 4.
Disclaimer: It is best to consult with your naturopathic doctor or healthcare provider before implementing anything new into yours or your child's healthcare plan. This information is not intended to treat or diagnose, and should not replace any currently prescribed protocols from your healthcare team. All information here is presented in an easy to read format; for those interested in evidence that supports this information, please contact us at ca@nadarra.health for citations or book an appointment to learn more.
