Parents who delay giving their babies allergenic foods could be
doing more harm than good, with a new Australian study showing the
rate of egg allergy significantly increases among toddlers who are
introduced to the food after 12 months of age.
The world-first study by the Murdoch Childrens Research
Institute and University of Melbourne found babies given egg after
12 months of age were up to five times more likely to develop egg
allergy as they grew older than infants introduced to egg at four
to six months of age.
Lead authors A/Professor Katie Allen and Jennifer Koplin said
the study added to growing evidence showing early introduction of
allergenic foods could be the best way to protect children against
allergies.
"Until recently, Australian and international guidelines
recommended that infants with a family history of allergy delay
introducing allergenic foods such as egg, peanut and nuts until up
to two to three years of age," Ms Koplin said.
"Our study suggests that babies who ingest these foods at an
earlier age may be less likely to develop food allergies as they
grow older. It seems that early introduction of egg may protect
against egg allergy, while delaying its introduction may put the
child at increased risk of developing an allergy."
The study, published online today by the Journal of Allergy and
Clinical Immunology, involved more than 2500 Victorian infants to
assess whether timing of egg introduction was associated with
increased or decreased risk of egg allergy.
Egg allergy is the most common food allergy in infants and
toddlers and can result in hives, vomiting, diarrhoea and, in some
circumstances, anaphylaxis.
Infants who were introduced to egg after 12 months of age had
triple the risk of egg allergy at 14-18 months of age than those
given egg at four to six months of age, irrespective of whether
they had a family history of allergy.
Giving babies cooked egg (boiled, scrambled, fried or poached)
proved more protective against allergy than egg in the baked form
(cakes, biscuits and similar products). Of babies aged four to six
months who were introduced to cooked egg, just 5.6 per cent
developed egg allergy compared with 27.6 per cent of those
introduced to cooked egg after 12 months.
The study found no link between egg allergy and the duration of
breastfeeding or timing of introduction of first solids.
A/Professor Allen said further research was needed to determine if
the study findings could also be true for other allergenic
foods.
"Confirmation that early introduction is protective for other
allergenic foods may help better inform parents in the future and
could have the potential to reverse the epidemic of childhood food
allergy," A/Professor Allen said.
"Food allergies often develop in early childhood and can have a
significant impact on quality of life for the child and their
family.
"Although children normally outgrow egg allergy, they remain at
increased risk of related conditions such as asthma and allergic
rhinitis in later life, as well as other food allergies such as
peanut and tree nut allergy which persist into adult life."
The research forms part of a wider study led by Professor Allen
at the Murdoch Childrens Research Institute to track food allergy
prevalence and causes among Victorian infants.