Can eating peanuts and eggs during pregnancy and breastfeeding protect infants from allergies?

A recently launched clinical trial sponsored by the US National Institutes of Health (NIH) is investigating whether mothers consuming peanuts and eggs during pregnancy and breastfeeding have a higher chance of protecting their babies from allergies to these foods. These are two of the most common early childhood food allergens. 

The researchers will explore why some infants’ immune systems already produce an antibody called immunoglobulin E (IgE) — a precursor of food allergy — even before they are introduced to peanuts or eggs.

Their clinical trial aims to demonstrate the efficacy of regularly feeding eggs and peanuts to expecting mothers, before and after birth, to protect their babies from developing IgE against those foods before they are introduced to these solid foods.

“Introducing food allergens such as peanut and egg into infants’ diets around four to six months of age has proven to be an important element of food allergy prevention, but this intervention comes too late for some children,” notes Alkis Togias, chief of the National Institute of Allergy and Infectious Diseases’ Allergy, Asthma, and Airway Biology Branch.

“We need additional, earlier strategies to help prevent the development of food allergies in children at high risk for them.”

The findings of this study may inform early childhood food allergy prevention strategies that precede the introduction of solid foods. Results are expected in September 2029.

Investigating prenatal interventions

The NIH reveals that around 8% of children in the US are affected by food allergies, which sometimes cause severe or life-threatening reactions.

However, there have been contradictory results among studies investigating the link between mothers consuming or avoiding allergenic foods during pregnancy or breastfeeding and their infants’ chance of developing food allergies.

The researchers are exploring why some infants’ immune systems already produce a precursor of a food allergy before they are introduced to peanuts or eggs.The new study will enroll pregnant mothers who are not allergic to peanuts or eggs, but whose babies are at high risk for food allergy because the mother has a parent, sibling, or child with allergic disease. Ultimately, the team aims to include 504 mother-infant pairs throughout the US.

The mothers will be assigned at random to either eat or avoid peanuts and eggs, beginning in their third trimester and continuing through breastfeeding. Those consuming the allergens will either receive guidance on the amounts of these foods to eat weekly.

All mothers are encouraged to feed their infants breast milk exclusively for at least three months.

Overall, the study aims to learn the proportion of infants in each group whose blood has IgE against peanut, egg, or both at age four to six months, before they consume those whole foods.

The mother-infant pairs will be followed until the children turn one year old.

Advances in food allergy research

Separate research on the development of food allergies in early life has revealed a “disturbing” gut microbiome trend among US infants that raises allergies and chronic health issues. Persephone Biosciences’ research has uncovered that 76% of US infants’ deficiency of gut Bifidobacteria has put them at risk for developing allergies, asthma, eczema, and dermatitis. The company plans to launch a synbiotic to tackle this crisis in response to these findings.

Decades of advice to avoid peanuts have made parents fearful of introducing peanuts at an early age. Another study contradicts this advice, finding that regularly feeding peanuts to infants up to five years old reduces the rate of allergy in adolescence by 71%.

In other research, the asthma drug omalizumab was found to make life safer for children with food allergies by preventing dangerous allergic responses following exposures to small quantities of allergy-triggering foods. After four months of monthly or bimonthly omalizumab injections, two-thirds of the study’s 118 participants dosed with the drug safely ate small amounts of their food allergens.