London - Feeding peanut butter and eggs to some babies from the age of three months reduces their chance of developing allergies, experts have found.
Current guidelines say babies should only be fed breastmilk until six months – at which solid foods should be introduced.
But the study suggests high-risk babies – those who have eczema or who tests reveal to be sensitive to certain foods – could benefit from early exposure to allergens.
Those given peanut butter at three months more than halved their risk of developing peanut allergies – from 33 to 14 percent. Early introduction of eggs was even more dramatic – a drop in allergy rate from 49 percent of babies first given eggs at six months, to 20 percent in those given them at three months.
The researchers, from King’s College London and St George’s University of London, said early introduction of allergenic foods could "curb the allergy epidemic" afflicting young children.
They said their findings should inform changes to the guidelines, which say foods such as peanuts, eggs, gluten and fish can be introduced from "around six months" – "one at a time and in small amounts [to] spot any reaction".
A growing body of evidence suggests that exposing babies to certain foods before this age could help prime their immune system.
Parents were once told to delay peanuts and eggs until the age of one. In 2008 that advice was updated to six months – as long as there is no family history of allergies. The new research, however, suggests that earlier exposure could help protect them from developing allergies later in life.
The academics tracked 1 300 babies. Half were introduced to six allergenic foods – peanut butter, egg, yogurt, wheat, sesame and fish – from three months of age alongside breastfeeding. The remainder were exclusively breastfed for six months when solid foods were introduced. The children were tracked for three years.
The findings, published in the Journal of Allergy and Clinical Immunology, showed egg and peanut allergies were reduced among high-risk babies but there were not enough babies who developed other food allergies to draw any further conclusions.
Among those who were not at high risk, the early introduction of allergenic food made no difference to developing a food allergy.
Study leader Professor Gideon Lack of King’s College London said: "If early introduction to certain allergenic foods became a part of these recommendations, we also have data that tells us what populations may need extra support when it comes to implementing the recommendations.
Dr Michael Perkin of St George’s added: "Early introduction of foods that causes allergies can significantly reduce the chances of high-risk infants developing peanut and egg allergy."
The number of British children allergic to peanuts has doubled in recent years to one in 50. Peanut allergy develops early in life, is rarely out-grown and there is no cure. At its most dangerous, it can cause fatal anaphylactic shock.