Could exposing young children to peanuts prevent allergies?

A new study by King’s College London and the University of California, San Francisco, found that feeding children peanuts regularly before age 5 reduced the rate of peanut allergy in adolescence by 71%.

The results of the study were published Tuesday in the NEJM Evidence Journal.

Researchers noted that peanuts can often cause significant allergic reactions, prompting fear from some parents. However, they say that the introduction of peanuts early in life can help build lasting tolerance.

“Decades of advice to avoid peanuts has made parents fearful of introducing peanuts at an early age,” King’s College professor Gideon Lack, who helped lead the research, said in a press release. “The evidence is clear that early introduction of peanut in infancy induces long-term tolerance and protects children from allergy well into adolescence.”

The study asked half of parents to regularly feed peanuts to children through age 5, while the other half were told to avoid peanuts. When the children reached age 6, both groups were free to eat peanuts if they chose.

The study said that 4.4% of 12-year-olds who were fed peanuts at a young age had peanut allergies, while 15.4% of 12-year-olds who were not fed peanuts early in life developed allergies.

The Cleveland Clinic says 1 in 50 children in the U.S. have a peanut allergy. About 20% of those with peanut allergies do eventually outgrow them.

Common symptoms of peanut allergies include diarrhea, difficulty breathing, hives or skin rash, nausea and vomiting, stomach cramps, and swelling, usually in the tongue or lips, the Cleveland Clinic said. Severe peanut allergies can be fatal.

The Cleveland Clinic says 17% of babies who never consumed foods that contained peanuts develop peanut allergies by age 5. For babies who consumed foods with peanuts, only 3% experienced a peanut allergy by age 5.

Researchers with King’s College say infants as young as 4 months old can be introduced to peanuts.

“The infant needs to be developmentally ready to start weaning and peanut should be introduced as a soft pureed paste or as peanut puffs,” George Du Toit, professor at King’s College, said.