Study Finds Peanut Consumption in Infancy May Prevent Peanut Allergy

Peanut butter on bread and peanuts next to it

The news: Researchers may soon have new advice for how parents can prevent their kids from developing serious peanut allergies, and the solution is "nuttier" than you may think. It turns out getting exposed to peanuts in small doses while you are a baby might be the biggest weapon against developing a more serious reaction to peanuts when you are an adult.

According to the new study published in the New England Journal of Medicine, the early introduction of peanuts dramatically decreases the risk of developing a serious allergy, by approximately 70% to 80%.

The study: The researchers assessed the effect of avoiding or introducing peanuts in more than 500 babies who were considered at risk for the allergy. The babies, who had either no or mild peanut sensitivity, were randomly assigned to a peanut consumption or peanut avoidance group. When the babies turned 5, the researchers gave them a peanut challenge to see if it would spur an allergic reaction.

The results were "striking," the team reported. At the end of the experiment, about 17% of the children who avoided peanuts developed a serious allergy, compared to only about 3% of those who didn't.

On top of that, of the babies who had no initial sensitivity to peanuts but were assigned to the peanut avoidance group, 13.7% developed a peanut allergy. For those placed in the consumption group, only 1.9% ended up developing the allergy.

The numbers were even higher for babies who presented with a mild sensitivity. Of those placed in the avoidance group, 35% developed an allergy. The percentage of babies who developed the allergy in the consumption group was only 10.6%.

The science: The immune system needs a taste of what it may have to fight — it's the same principle behind vaccines. After getting exposed to specific antigens of harmful organisms like viruses and bacteria, the immune system designs a defense system aimed to target those antigens should they ever enter your body again. This is called acquired immunity, and a similar mechanism may be at play when it comes to a peanut allergy.

Why this matters: What you eat now matters later. "Peanut allergy has become the leading cause of anaphylaxis and death related to food allergy in the United States," the researchers write. With this new science on developing peanut allergies, we may be able to at least curb this problem.

Over the years, peanuts have become increasingly vilified and are no longer welcome in many schools or even airlines. Unfortunately, this increased alertness may be causing the problem it's trying to avoid. In the U.S., peanut allergies in minors have increased from just .4% in 1997 to 1.4% in 2008 and a disconcerting 2% in 2010.

But the team isn't ready to jump the gun on new advice just yet. There are still a lot of questions to answer. For instance, how much exposure is needed to keep a serious peanut allergy from developing into adulthood? Also, what happens if a parent stops giving their baby peanut products for a while? Does that mean that the tolerance goes away?

It might be too late for older peanut allergy sufferers, but since studies show that the trait might be heritable, the new research points to a way that babies born to parents with the allergy can still enjoy the delight of a PB&J sandwich from time to time.