allergies
April 04, 2019
Figure 1: In one of the largest trials studying peanut exposure therapy, researchers found that early exposure to peanuts dramatically reduces risk of allergies in kids. Kids exposed to peanuts at a young age had a prevalence of 1.9%, which was significantly lower than the 13.7% prevalence in kids who avoided peanuts.
Allergies are probably one of the least understood fields in medicine. The immune system is immensely complex and we’re just starting to scratch the surface.
Traditionally, kids at risk of peanut allergies were kept away from peanuts. However, a new study in the New England Journal of Medicine turns this paradigm on its head. The study showed that we’ve been doing it completely wrong: kids at risk of allergies should be exposed to peanut protein, not kept away.
Researchers recruited 640 infants and randomized them to either eat lots of peanut butter or to avoid peanut butter.
Overall, 13.7% of kids that were assigned to avoid peanut butter developed peanut allergies by age 5. Among the kids who ate peanut butter, only 1.9% developed allergies. This suggests that many peanut allergies in kids who have been kept away from peanut butter are in fact completely avoidable.
Figure 2: Peanut Exposure in High Risk Infants. Infants at highest risk of peanut allergies, as measured by pin prick test, had a 36.3% peanut allergy rate if randomized to avoid peanut protein. Kids assigned to peanut exposure therapy had a 10.6% allergy rate.
What about infants at a higher risk of allergies, should they be exposed to peanut butter as well?
This study identified kids at high risk of developing peanut allergies with a pin prick test, which tests whether the body reacts to a tiny amount of allergen pricked into the skin.
The study results among these kids suggest that kids at high risk should absolutely be exposed to peanut protein. Among high risk infants who were randomly assigned to avoid peanut butter, 36.3% ended up developing a peanut allergy by age 5. Among high risk infants assigned to consume peanut butter, only 10.6% developed peanut allergies.
This result was unexpected by many, and was the beginning of a major shift in how doctors view peanut allergies:
Out findings showed that early sustained consumption of peanut products was associated with a substantial and significant decrease in the development of peanut allergy in high-risk infants. Conversely, peanut avoidance was associated with a greater frequency of clinical peanut allergy than was peanut consumption, which raises questions about the usefulness of deliberate avoidance of peanuts as a strategy to prevent allergy.
Source: Randomized Trial of Peanut Consumption in Infants at Risk for Peanut Allergy
Figure 3: Peanut Exposure Protocol. Peanut exposure therapy involves giving kids at least 6 grams of peanut protein per week spread over at least 3 meals. In the NEJM study, kids were given either Bamba, a peanut snack, or smooth peanut butter.
The doctors achieved this significant improvement with a surprisingly simple procedure.
Kids were given at least 6 grams of peanut protein a week, spread over 3 days. In the study, they used a product called Bamba, but smooth peanut butter should work as well.
They were consistently given this protein until age 5, when they were tested for peanut allergies.
Figure 4: Peanut Exposure Therapy Recommendations from the American Academy of Pediatrics.
This remarkable result from 2015 has already begun changing the way doctors practice.
After this study was published, the American Academy of Pediatrics introduced a new set of guidelines for treating peanut allergies.
Estimated to affect 1%-2% of children, peanut allergy often is severe and lifelong. The new guidelines recommend early introduction of peanut protein for infants who are at increased risk of developing the allergy. They caution, however, that peanuts and peanut butter are choking hazards, and advise on forms that are safe for infants such as peanut butter smoothed into pureed fruits or vegetables.
Source: New guidelines detail use of ‘infant-safe’ peanut to prevent allergy
Briefly, the guidelines suggest that most kids without risk factors for peanut allergies can eat peanut butter whenever it’s preferred by or convenient for the family.
Kids with egg allergies or severe eczema, which puts them at the highest risk of peanut allergies, should get tested for allergies by their doctors. Ideally, they should start getting peanut protein when they are 4-6 months old.
Kids with mild to moderate eczema, which indicates a medium risk of peanut allergies, should start eating peanuts when they are 6 months old.
Source: New guidelines detail use of ‘infant-safe’ peanut to prevent allergy
Figure 5: Peanut Allergy Prevalence in the United States. Peanut Allergies have grown in prevalence
This study addressed one of fastest growing pediatric conditions in the United States.
Peanut allergies are one of the most common allergies. Nearly 1.5% of children and teenagers report having a peanut allergy in the United States according to the latest data, though this can vary by study.
With this very simple new therapy, more kids can hopefully avoid developing peanut allergies.