Two studies have been published relating to babies and the “atopic march”, the progression of allergic diseases including atopic dermatitis (eczema), food allergy, allergic rhinitis (hay fever) and asthma.
The first, a study by the University of Western Australia, found that when breastfeeding mothers consumed eggs, their babies were less likely to develop egg allergy.
Study leader Professor Valerie Verhasselt, from UWA’s School of Molecular Sciences, said the findings were important because in western countries up to 10% of children already have a food allergy at one year of age.
“Among high-risk population, one third are already sensitised to egg at 4 months of age and may experience severe allergic reaction if egg is introduced into their diet,” Professor Verhasselt said.
“Our study shows that protection could be induced through breastfeeding and before the introduction of any solid food to the child’s diet.”
The researchers were able to discover that some breastmilk components were more successful than others in preventing allergy.
“Ten years ago, we demonstrated in an animal model that you could educate the immune system of a baby to accept egg protein as well as protect the baby from egg allergy later on,” Professor Verhasselt said.
“Our new study shows for the first time that this may also happen in humans. We’ve found that cases of egg allergy in children are four times less likely when they have been exposed to breastmilk containing egg protein, compared to those exposed to breastmilk without detectable egg protein.”
The team at UWA was also able to uncover that some mothers shed house dust mite allergens in breastmilk. House dust mite allergens are known to be responsible for respiratory allergies such as rhinitis and asthma.
“By conducting pre-clinical experiments, we demonstrated the very new concept that respiratory allergens in a baby’s gut may represent a risk factor for food allergies,” Professor Verhasselt said.
“Targeting respiratory allergens may be essential for prevention of egg allergy in breastfed children.”
Professor Verhasselt, who is also the Larssen-Rosenquist Chair in Human Lactology at UWA, said the studies, published in the journals Allergy and Journal of Allergy and Clinical Immunology, showed researchers were on the path to preventing egg allergy through breastfeeding.
“Our data still needs to be confirmed in large randomised control trials to bring formal proof of this promising new approach of exposing babies to egg protein through breastmilk,” she said.
“Our research is aiming to find ways to prevent allergy and stop this modern world epidemic,” Professor Verhasselt said.
The other study, recently published in The Lancet, followed 1394 term newborns at “high risk” of developing eczema in a randomized controlled trial in 12 hospitals and four primary care sites across the UK. High risk was defined as having one first-degree relative diagnosed with eczema, allergic rhinitis, or asthma.
The newborns were randomly assigned to one of two groups: those that received a daily emollient for the first year (Diprobase cream or DoubleBase gel) and those that didn’t. The study then looked at the development of eczema by the participants at two years of age.
At age two, eczema was present in 139 (23%) of 598 infants with outcome data collected in the emollient group and 150 (25%) of 612 infants in the control group.
The researchers summarized their findings as follows:
We found no evidence that daily emollient during the first year of life prevents eczema in high-risk children and some evidence to suggest an increased risk of skin infections. Our study shows that families with eczema, asthma, or allergic rhinitis should not use daily emollients to try and prevent eczema in their newborn.