Latest allergy advice says mothers should eat oily fish and feed peanuts to babies

Expectant mothers are being told to regularly eat fish and give their babies peanuts thanks to studies that have upended what we thought we knew about allergies.

Hospital admissions for severe allergic reactions have doubled over the past decade in Australia, the UK and the US.
Hospital admissions for severe allergic reactions have doubled over the past decade in Australia, the UK and the US. Photo: Getty Images

Australia's peak medical body for allergies has changed its guidelines for pregnant women and infants, updating advice for the first time in half a decade, to bring it in line with research which shows that, among other things, early exposure is the best prevention.

Pregnant women are also advised to eat oily fish up to three times a week and to try breastfeeding for at least six months to prevent childhood eczema, according to the Australasian Society of Clinical Immunology and Allergy guidelines released on Monday.

Mothers of high-risk infants should introduce peanuts (in the form of peanut butter or crushed nuts) and cooked egg into the baby's diet before its first birthday and are told not to buy expensive hydrolysed baby formula to prevent allergies.

The advice follows a study published in the New England Journal of Medicine last year which found babies exposed to peanuts in their first 11 months were less likely to develop an allergy than their peers and research published in the BMJ (formerly the British Medical Journal) last week showing hypoallergenic baby formula did not prevent allergies.


The new ASCIA guidelines include:

  • Up to three serves of oily fish a week during pregnancy and breastfeeding may be beneficial in preventing eczema in early life.
  • There is no consistent, convincing evidence to support that notion that hydrolysed formulas (usually labelled HA or hypoallergenic) assists in allergy prevention in infants or children.
  • There is evidence that for infants at high risk of food allergies, such as those with severe eczema or who already had a food allergy reaction to egg, introduction of regular peanut before 12 months of age can reduce subsequent peanut allergy.
  • It is not recommended that infants are fed raw egg, however there is moderate evidence for the introduction of cooked egg into the diet of infants with a family history of allergy before 8 months of age to try and reduced the risk of egg allergy.

Professor Dianne Campbell, Chair of the ASCIA Paediatric Committee, said there were ways for pregnant women to eat fish without also increasing the risk of consuming harmful mercury, including sticking to farmed fish.

"If you choose not to breastfeed, or you can't breastfeed, there is no evidence to suggest that there's any benefit to any special formula over just a normal, commercial-standard cows' milk or soy formula," Professor Campbell said.

Recent studies have also found "significant benefit" in introducing peanuts within the first year of life for babies who are high-risk for peanut allergies and within eight months for egg allergies, Professor Campbell said.

Food allergies have increased significantly in the past 25 years and affect 10 per cent of babies, 4-8 per cent of children aged up to five years old and about 2 per cent of adults, according to the ASCIA.

Hospital admissions for severe allergic reactions have doubled over the past decade in Australia, the UK and the US.

"I think there is a strong feeling that the delayed introduction of allergenic foods, particularly for babies who were at some risk of allergic disease has actually increased the rates of food allergy," Professor Campbell said.

"That is unfortunately not the only thing that contributes to the rise of allergic disease around the world but in countries like Australia and the UK and the US where food allergies are very prevalent then [early introduction] will have a significant impact."

Parents are advised to speak with their GP before changing a child's diet.