Peanut allergies are becoming more common among children.  It is estimated that  3.2% of children have peanut allergies.  In an effort to prevent this allergy, the Canadian Paediatric Society has recommended the introduction of peanuts and other allergenic foods around 6 months of age. Research has interestingly shown that what mothers eat during pregnancy may influence their child’s taste preferences later on.  Could maternal consumption of highly allergenic foods like peanuts reduce the incidence of peanut allergy later on? 

Conflicting Evidence

Early studies trying to answer this question found that mothers who consumed peanuts during pregnancy had an increased likelihood of having a child who was allergic to peanuts. However, many of the children evaluated in these studies had other allergies as well, making the study hard to interpret.  On the other hand, additional studies showed that there was likely no significant association between peanut ingestion during pregnancy and later childhood allergy. Some researchers even measured allergy-specific proteins in cord blood of women who consumed peanuts and could not find any meaningful amounts. 

In 2013, the Canadian Paediatric Society released guidelines stating that pregnant women should not restrict their peanut intake in an effort to prevent allergy. Since their statement, a study followed over 10,000 mother-infant pairs and showed that infants whose mothers who had increased peanut consumption during pregnancy were actually less likely to have peanut allergies later in their childhood. This study was helpful for researchers to eliminate some bias and conflicting evidence seen in earlier research. 

There is yet to be enough information on how peanut consumption during breastfeeding impacts infants’ allergy status later. There are a lot of factors at play when it comes to your child’s response to foods beyond your consumption during pregnancy!

Bottom Line

There isn’t enough evidence to make a claim that increased peanut intake while pregnant will successfully prevent childhood peanut allergies. What research tells us is that there is no need to restrict or avoid peanuts as a means of allergy prevention.  If peanuts are part of your nutritious pregnancy diet, then there is no harm in keeping it on the grocery list! If you don’t eat peanuts or have a known allergy to them, then their absence from your diet will likely not disadvantage your child’s growth or tolerance later. 

This post was co-authored by Marissa Nahirney, a fourth year medical student at the University of Alberta and Dr. Yuliya Koledenko, a family physician with special interest in obstetrical care. 

The post was reviewed and edited by Erin Manchuk, BScPharm, BCGP and Stephanie Liu, MD, MSc, CCFP, BHSc.