Can food allergies be prevented?

A baby is more likely to develop a food allergy if their parents or siblings have allergies. Recent research is providing new insights into how it may be possible to prevent such allergies from developing.

European expert groups, in line with WHO guidelines, recommend exclusive breastfeeding (no solid foods or supplementary infant formula) for the first four to six months of life.

If breastfeeding for infants with a high risk of developing allergies is not possible, hypoallergenic formula should be used to reduce the likelihood of developing allergies.

They also recommend that pregnant and breastfeeding women do not need to eat a special diet.

Diet of the mother during pregnancy and breastfeeding

There is no evidence that indicates that women should modify their diet when they areeither pregnant or breasftfeeding, or take supplements, like probiotics,to prevent food allergy in their children.

There is a need for further research in the area to discover whether, for example, taking fish oil supplements during pregnancy can help prevent food allergy developing in children. Currently,some studies suggest they may be beneficial while others suggest the opposite.

Introduction of allergenic foods in childhood

It is generally accepted that by around 6 months of age,infants are ready for foods other than breastmilk or infant formula. The way in which complementary foodsare introducedinto an infant’sdiet needs to take into consideration many factors, includingtheir developmental readinessand nutritional requirements,as well as parental needs.

The evidence is that delaying the introductionof foodssuch as peanut or hen’s egg beyond 6-12 months of age can increase the risk of infants becoming allergic to those foods.

A landmark study,known as the Learning Early About Peanut (LEAP) and Enquiring About Tolerance (EAT) trials, have provided evidence supporting early introduction of peanut and other foods (between four and 11 months) in the prevention of food allergy in infants who are at high risk (as defined by early onset eczema or co-existing egg allergy).

However, in the UK, the Scientific Advisory Committee on Nutrition (SACN) has concluded that there is insufficient evidence that introductionof peanut or hen’s egg before 6 months of age has any benefit compared to introduction from around 6monthsold.

For similar reasons, the European Academy of Allergy Clinical Immunology considered that evidence was lacking tomake specific recommendations about the timing of the introduction of complementary foods and individual solid foods to prevent food allergy. Instead, the Academy recommended that complementary foods be introduced into the diets of all infants from 4 to 6 months of age according to standard local practices and the needs of the infant..

However, in the US, the National Institute of Allergy and Infectious Diseases hastaken a different approach and amended itsguidelines for prevention of peanut allergyin the light of the LEAP study results. This takes a risk-based approach where infants at high risk of developing peanut allergy are intorduced to peanut from the age of 4-6 months.