Giving babies solid food
while still breastfeeding, and waiting until 17 weeks to do so, might protect
the infants from food allergies, British researchers say.
The overlap between
starting solid foods while still breastfeeding teaches the immune system that
food is safe and prevents food allergies, the researchers theorised.
continue to breastfeed beyond introducing solids into the diet so the immune
system can benefit from the immunological factors in breast milk that educate
the immune system," said lead researcher Kate Grimshaw, a research fellow
and allergy specialist at the University of Southampton.
"My theory was that if
food allergens – those things that infants actually become allergic to – aren't
there at the same time as the breast milk, the breast milk can't educate the
immune system," she said.
The researchers said they
identified when this process is likely to begin. "Introducing solid food
before 17 weeks was associated with an increased risk of children developing
food allergies," Grimshaw said.
Although other studies have
found an association between when solid food is started and the risk for food
allergies, none has established when infants are most at risk for developing
food allergies, she said.
"We have pinned down
the risky period as being before 17 weeks," Grimshaw said.
The report was published in
the online edition of the journal Paediatrics.
At least one expert
questioned the conclusions, however, saying the study doesn't prove Grimshaw's
Hernandez-Trujillo, director of allergy and immunology at Miami Children's
Hospital, said the study supports the importance of breast-feeding, but doesn't
nail down why food allergies develop.
still don't have all the answers when it comes to food allergies,"
Hernandez-Trujillo said. "It appears that breast-feeding may be
protective, but we still don't know why."
Why breast milk might
protect children from food allergies isn't really known, she said. "It may
have to do with [antibodies], but that would be totally speculative," she
good for the child in many different ways, and it may be helpful in possibly
preventing food allergies," she said.
Cow's milk protein
For the study, Grimshaw and
her colleagues looked at the diets of 41 children who developed food allergies
by age 2. They compared that with foods eaten by 82 children without food
The researchers found that
the children with food allergies were started on solid foods earlier (at about
16 weeks or younger) than children without allergies. They also were less
likely to be breastfeeding when introduced to any form of cow's milk protein,
which is found in cow's milk and some processed foods.
"This study supports
the current American Academy of Paediatrics’ allergy-prevention recommendations
and the European Society of Paediatric Gastroenterology, Hepatology and
Nutrition's recommendations on complementary feeding to not introduce solid
[foods] before four to six months of age," the researchers said.
"It also supports the
American Academy of Paediatrics’ breastfeeding recommendations that
breastfeeding should continue while solid [foods] are introduced into the diet
and that breastfeeding should continue for one year or longer, as mutually
desired by mother and infant," they said.
For more information on
breastfeeding, visit the US
National Library of Medicine.