Feeding children peanut products from infancy until the age of five cuts their risk of developing a peanut allergy into early adolescence, researchers say.
Children who ate peanut pastes or puffed peanut snacks regularly from four to six months onwards were 71% less likely to have a peanut allergy at age 13 than those who avoided peanuts, pointing to a long-lasting effect of early peanut consumption.
The simple dietary intervention could prevent about 10,000 cases of potentially life-threatening peanut allergies each year in the UK alone, doctors said, and cut global cases by 100,000 annually.
Gideon Lack, professor of paediatric allergy at King’s College London, said decades of advice to avoid peanuts had made parents wary of giving them to their children from such an early age. But he said the evidence was now clear that early exposure to peanuts provided long-term protection against the allergy.
“I strongly recommend that babies are introduced to peanuts by four months if they have eczema and by six months if they don’t have eczema,” Lack told the Guardian. Babies with eczema have a greater risk of developing peanut allergies, probably because traces of the food can penetrate the skin more easily and be targeted by the immune system.
Rates of peanut allergy have risen in many western countries in recent decades. One in 50 children in the UK now have the allergy, with about 14,000 newly diagnosed each year. Although 20% of children typically grow out of the allergy, for the rest the condition can mean avoiding peanuts for life and the inevitable worry of a severe allergic reaction if they accidentally come into contact with the food.
Despite their name, peanuts are legumes and come from a different family of plants to tree nuts such as almonds, Brazil nuts, cashews, pistachios and walnuts. About a third of children with peanut allergy will have an allergy to at least one type of tree nut.
Previous work by the same researchers found that regular consumption of peanut products from infancy reduced the risk of peanut allergy at age five by 81%, compared with children who avoided peanuts for the same period. The latest study, known as the Leap-Trio trial, followed 508 of the children to an average age of 13, during which time they were free to eat or avoid peanuts as they wished.
The trial found that children in the early peanut consumption group had a 71% lower risk of peanut allergy compared with those in the peanut avoidance group. As expected, a small percentage of the children naturally grew out of their allergy. The results published in NEJM Evidence show that the protection remained intact regardless of the children’s peanut-eating habits after the age of five.
Lack said there was a “double advantage” to starting children on peanut products early. “You will prevent the vast majority of peanut allergy, but for those cases where you aren’t able to prevent it, you can identify the children earlier when treating them is much easier,” he said.
“Once they are at seven, eight, nine months of age, you have really missed the boat. But even if you do miss the boat, you identify children who have peanut allergy early and can treat them with immunotherapy.”
The researchers said peanut butter or peanut puffs could be given to children who were still breastfeeding once they were able to manage soft foods.
The aim should be to give the equivalent of a heaped teaspoon of peanut butter three times a week. While whole or chopped peanuts should be avoided because of the choking risk, peanut puffs can be ground into a paste suitable for babies.
