A new study reports what might seem like a strange, but welcome, finding: by feeding peanuts to infants, parents may actually prevent the development of a peanut allergy. Published in The New England Journal of Medicine, the study tracked 530 infants who were 4 to 11 months old and did not have a peanut allergy, but who were at a high risk of developing one. The infants were then divided into two groups; one group of infants consumed at least 6 grams of peanut protein per week (equivalent to about 24 peanuts), distributed in three or more meals, until they were 5 years old. The other group of infants avoided peanuts until they were 5 years old. For a different part of the study, researchers looked at 98 other infants who not only had a high risk for a peanut allergy, but also exhibited some early sensitivity to peanuts. These children were also divided into a consumption group and an avoidance group. Here are the results from both parts of the study after tracking the children for a number of years:

• Among the infants who were at high risk for a peanut allergy, only 1.9% of those who ate peanuts developed an allergy, whereas 13.7% of those who avoided peanuts developed an allergy.
• Among the infants who were already sensitive to peanuts, only 10.6% of those who ate peanuts developed an allergy, whereas 35.3% of those who avoided peanuts developed an allergy.

The study and its findings are notable for a few reasons. First, this was a randomised controlled trial (though not placebo-controlled), lending strong support to its conclusions. Second, the findings are consistent with observational data relating to peanut allergies. In particular, researchers have noted that Israeli children, who start eating peanuts when they are around 7 months old, have about 1/10^th the rate of peanut allergy as Jewish children in the UK of similar ancestry, who typically do not eat peanuts in their first year of life. Third, the findings suggest a possible way to combat, and to possibly explain, the rising rates of peanut allergy in Western countries.

Source: The New England Journal of Medicine