Eating eggs and peanuts during pregnancy does not reduce infant allergies

Despite theories that high intake of some foods during pregnancy and breastfeeding could help reduce food allergies in children, researchers have found this is not the case for eggs and peanuts.

They say their findings will enable healthcare practitioners to reassure pregnant and breastfeeding parents that high levels of egg and peanut consumption is not detrimental, but nor will it reduce the risk of their baby developing egg and peanut allergies.

Australia has one of the highest rates of food allergies in the world. Peanut allergies affect around 3% of infants while egg allergies affect almost 9%.

Researchers say understanding how these develop is key to improving prevention and treatment.

The randomised controlled trial, undertaken by The Kids Research Institute Australia, included 2137 pregnant and breastfeeding women across four Australian states.

All the infants involved in the study had at least two family members with a history of allergic disease, which increased their likelihood of developing food allergies.

Half the women were assigned a high egg and peanut diet of at least six eggs and 60 peanuts per week, and the other half were assigned to a control group of no more than three eggs and 30 peanuts per week.

Lead author and Head of the Nutrition in Early Life team at The Kids Associate Professor Debbie Palmer said the results were not what researchers had expected.

“We had expected that the mothers eating higher amounts of eggs and peanuts during pregnancy and breastfeeding would have reduced egg and peanut allergies in their babies,” she said.

“However, we found no difference between the two groups. There were also no indications that higher maternal egg and peanut ingestion reduced, or increased, the risk of infant egg or peanut sensitisation, egg or peanut allergy individually, or eczema.

“For food allergy prevention, our best current advice is to include well-cooked egg – such as mashed hard-boiled egg – and smooth peanut butter mixed in with the baby's solid foods, starting soon after they have commenced eating solid foods, and continuing to include egg and peanut regularly in the baby's diet at least once a week.”

The PrEggNut study was published in The New England Journal of Medicine.

Executive Director of The Kids Professor Caroline Homer said the study added valuable evidence to the growing understanding of how allergies developed.

“Research like this helps build the evidence needed to develop more effective prevention strategies and improve outcomes for children and families.”