Early exposure to peanuts in infancy could see allergy ‘plummet’

Research from King’s College London (KCL) has found that exposing children to peanuts from infancy to age five reduced the rate of peanut allergy in adolescence by 71 per cent.

The new study adds to evidence that the early introduction of peanuts and peanut products in infancy induces long-term tolerance and protects adolescents from allergy.

The researchers say that early peanut consumption will result in peanut allergies plummeting and could prevent more than 100,000 new cases of peanut allergy every year worldwide.

The study, which was sponsored and co-funded by the US National Institutes of Health’s National Institute of Allergy and Infectious Diseases (NIAID), is published in NEJM Evidence.

In Western countries such as North America, the UK, Western Europe and Australia, rates of peanut allergy amongst young people are currently around two per cent but are rising. Life-threatening allergic reactions and conflicting health advice have led parents and caregivers to be fearful of introducing peanuts into young children’s diets.

The trial, known as the LEAP-Trio Study, built on the findings of the Learning Early About Peanut Allergy (LEAP) clinical trial. The initial study looked at the impact of introducing peanuts to children from infancy to five years of age, using a trial group, who were exposed to peanuts and a control group who were not.

Findings showed that children who ate peanuts and peanut products from an early age had an 81 per cent reduced risk of allergy at age five.

Building on this work, the researchers followed both groups of children between the ages of six and 12. Children could eat peanuts in whatever amount and frequency they wanted during that period. The adolescents were tested for peanut allergy primarily through an oral food challenge, which involved giving participants gradually increasing amounts of peanut in a carefully controlled setting to determine if they could safely consume at least 5 grams of peanut, the equivalent of more than 20 peanuts. The study team also surveyed participants about their recent patterns of peanut consumption, which were verified through measurements of peanut in dust from participants’ beds, a technique previously validated by LEAP investigators.

The early avoidance group showed a peanut allergy level of 15.4 per cent by the age of 12. This was compared to 4.4 per cent in the children who had eaten peanuts from an early age. Following the children through to age 12 showed that regular, early peanut consumption reduces the risk of peanut allergy in adolescence by 71 per cent compared to early peanut avoidance.

Lead investigator Professor Gideon Lack from KCL said: ‘Decades of advice to avoid peanuts has made parents fearful of introducing peanuts at an early age. The evidence is clear that early introduction of peanut in infancy induces long-term tolerance and protects children from allergy well into adolescence. This simple intervention will make a remarkable difference to future generations and see peanut allergies plummet.’

Throughout childhood, the overall consumption of peanuts and peanut products was higher in the group who had been exposed to peanuts between infancy and age five. However, during the period of six to 12 years of age, peanut consumption varied widely between the two groups and included periods of not eating peanuts for some participants in both groups. The findings suggest that the protective effect of early peanut consumption lasts, without the need to eat peanut products consistently throughout childhood and early adolescence.

Professor George Du Toit, Co-Lead Investigator from KCL, said: ‘This is a safe and highly effective intervention which can be implemented as early as four months of age. The infant needs to be developmentally ready to start weaning, and peanut should be introduced as a soft pureed paste or as peanut puffs.’