Peanut allergies are so common in the United States that peanut restrictions in workplaces or schools have almost come to be expected. And for good reason: Scientists have watched the prevalence of peanut allergies grow steadily, tripling in the US from .4 percent of households surveyed in 1997 to 1.4 percent in 2008. And though some doctors encourage parents to tackle the issue head on through early exposure, it’s hard to know how many are actually willing to do so. Meanwhile, like all true food allergies, a peanut allergy can be deadly, triggering anaphylaxis (which may even present without identifiable skin symptoms like hives).
But now, it appears that scientists have found a way to turn the tide. In a small but very promising study out of Australia, published in The Lancet Child & Adolescent Health, researchers were able to confirm the success of oral immunotherapy against peanuts, resulting in a lasting peanut tolerance. The study served as a follow-up to an earlier, placebo-controlled experiment against peanut allergies using a combination of peanuts and probiotics as treatment. Four years later, 48 out of 56 eligible participants from the original immunization trial—half from the peanut-treated group and half from the placebo treated group— were tested again for their peanut tolerance.
In the follow-up study, 20 out of the 24 of the peanut-treated participants reported that they hadn’t experienced an allergic reaction since the original trial four years ago, with 16 out of 24 still actually eating peanuts. In the placebo-treated group, only one participant reported that they had continued eating peanuts.
“Our findings show that combined probiotic and peanut oral immunotherapy provides long-lasting clinical benefit compared with placebo,” the authors wrote, “with two-thirds of treated participants symptom free after peanut ingestion 4 years after completing treatment.”
Given that recent research has indicated that it’s not just young children who can develop new allergies, these findings have the potential to drive a number of new and larger immunization trials, which is good news for sufferers of peanut allergies everywhere. If we're lucky, a world in which peanut butter is accessible to all is in our future.