You’ve probably already seen headlines about a study showing that feeding children small amounts of peanut products in the first 5 years of life can prevent the development of peanut allergy. The study was conducted in the U.K., led by Gideon Lack of King’s College London, and was published this week in the New England Journal of Medicine (free full text available here).1
Why is this study important?
Food allergies are on the rise in Western countries, and peanut allergy is one of the scariest. In the U.S., more than 2% of children and their families are now living with a peanut allergy, representing a 5-fold increase in prevalence since 1997.2,3 And this allergy isn’t just an inconvenience; it’s now the biggest cause of anaphylaxis and death related to food allergy in the U.S.4 This is a huge concern to parents wondering when and how to introduce peanuts to their kids, but the advice on this matter has been really confusing over the last 15 years.
In 2000, the AAP recommended delaying the introduction of peanut and other commonly allergenic foods (i.e., wheat, eggs, fish, cow’s milk) until at least the first birthday and until age 3 for kids thought to be high-risk for allergy.5 While this advice may have seemed reasonable, it was never based on good evidence – just a best guess based on knowledge at the time.
Meanwhile, the incidence of food allergies continued to climb, and epidemiological evidence emerged that avoiding allergens might backfire. In 2008, the AAP issued new guidelines stating that there was no evidence that delaying introduction of solid foods, including common allergens, beyond 4 to 6 months of age would protect children from developing allergies.6 This document was intentionally vague, because at the time, there weren’t any studies to give more specific guidance on when to introduce what, in what amounts, etc. And this flip-flop in advice, which was also mirrored in many other countries, has left a lot of parents confused.
Gideon Lack and colleagues published a study in 2008 that found that the incidence of peanut allergy among Jewish children in the U.K. was 10-fold higher compared with those growing up in Israel.7 Comparing the mean age of introduction of peanut protein between the two countries, they found that babies in Israel were commonly introduced to peanut in their first year, while babies in the U.K. were not. This led them to their hypothesis that early exposure to peanut might help prevent the development of peanut allergy, and that’s what the current study tested.
How was this study conducted?
The researchers recruited babies between the ages of 4 and 11 months that were high risk for developing peanut allergy because they had severe eczema, egg allergy, or both. Continue reading