Peanut allergy is one of the most common allergies in the United States, affecting 2.5% of children. In 2015, results from a groundbreaking study called the Learning Early About Peanuts (LEAP) study, showed that giving peanuts to infants earlier than previously thought can reduce the development of peanut allergy later in life. Before the results of the LEAP study came out, it was common for pediatricians to tell parents to hold off until about three years of age or later to give any form of peanut.
It was a chance encounter at a scientific conference outside of the US that kickstarted the LEAP study. A doctor at the conference asked people about peanut allergy and found that hardly anyone raised their hand as having kids with peanut allergy, a big difference to what was seen in the US. It turns out that in the country where this conference was being held, it was common for parents to feed their kids Bamba, a type of peanut puff, from a very young age. Peanuts were one of the first foods these kids were eating.
After learning this, the doctor worked on the LEAP study to investigate infant exposure to peanuts. Based on this research, if a child is unlikely to have a peanut allergy, they can eat peanuts early in life and are less likely to go on to develop a peanut allergy. Thanks to this finding, pediatricians now recommend that infants get peanut puffs, peanut butter, or something similar in small amounts when they start eating solid foods, far earlier than previously recommended.
Peanut Allergy
Research has also helped to explain why this happens. When you invite the peanut into your body through your mouth, you’re inviting it through the front door like a guest. Since the peanut was let in willingly, your immune system tolerates it and sees it as something that’s not dangerous. However, since peanuts are all around us, if you wait until you are older than three to eat peanuts, the peanut might have already come in through an abrasion or a cut, more like an intruder than a guest. In this case, your body will see peanuts as foreign, and your immune system will respond.
The LEAP study found that when kids invite the peanut in the front door, like a guest, it is tolerated by their mucosal system, which is part of the immune system that lines the respiratory and gastrointestinal tracts. However, if the peanut comes in through a break in the skin before it comes in the front door, like it’s breaking in through the window, then they are more likely to have an allergy. This is not always the case as children can still be predisposed to peanut allergy through genetics, environmental factors, and all kinds of other things, but the LEAP study does show that early introduction of peanuts can reduce the prevalence of peanut allergy in children.