The significant rise in peanut allergies in recent years has puzzled physicians and scientists. In the past decade, peanut allergies have quadrupled in the United States. The scientific community has started to suspect that doctors’ recommendations to parents, regarding when to feed their children peanuts, could be partly to blame for the rise in peanut allergy incidence.
Doctors used to tell parents to avoid feeding their children foods that are often associated with allergies, such as peanuts, eggs, and fish, until their children were about three years old. The idea behind this protocol was that young immune systems may not yet be ready to deal with these potentially problematic foods. In 2008, however, these recommendations changed when the American Academy of Pediatrics decided that delaying the introduction of these foods may in fact increase the chances that allergies develop.
Last year, a long-term study known as LEAP showing that 5 year olds were 81% less likely to be allergic to peanuts if they ate peanuts products like peanut butter before they were 11 months old was published in the New England Journal of Medicine Last month, another study, known as LEAP-On, was published in the same prestigious medical journal that further supports the idea that exposing kids to peanuts early may actually be an effective way to prevent the development of peanut allergies. In addition, the study demonstrated other positive effects that peanuts may have on health.
As in the previous study, this recent research focused on children with a high risk for developing an allergy to peanuts. They found that kids who ate peanut products from infancy until they were 5 years old could avoid peanuts for a full year without affecting their risk of developing a peanut allergy. There were 550 study participants who were asked not to ingest peanut products for one year, from the age of 5 to the age of 6. Once they were 6, these children were tested for peanut allergies, and 21.5% of those who had always refrained from ingesting peanuts were found to be allergic to them, whereas only 2.4% of those who ate peanuts in their first 5 years of life were now allergic.
Enough exposure early on in life therefore seemed sufficient enough to allow children’s immune systems to recognize peanuts as innocuous in the long-term, even if peanut exposure was not consistent afterward. This new study builds on the previous finding that early peanut exposure reduces the risk of developing peanut allergy by showing that this protection can last even through a subsequent avoidance phase.
Several other problems often seen in children, including stomach bugs, eczema, lower respiratory tract infections, and near-sightedness were also found to be lower in the children who ingested peanut products from infancy to the age of 5. Given the latest findings on the relationship between peanut exposure and the likelihood of developing peanut allergies, as well as the correlation between peanut exposure and other health benefits, the American Academy of Pediatrics are working to develop updated guidelines. For now, pediatricians are told to suggest to parents that children be introduced to peanuts between the ages of 4 and 11 months if the children are at risk for developing peanut allergies.
Another recent study, known as EAT, looked at the ability of early exposure to other foods, such as egg, fish, milk, and wheat to desensitize children to allergies to these foods. Though the study clearly showed that early exposure to egg could reduce rates of the development of egg allergy, the findings for the other foods were less clear. Researchers plan to improve their study designs so that they can clarify the specific impacts of early exposures to problematic foods and determine any differences that may exist in the pattern of allergy development for different foods.