- A new study reports that about 20 percent of U.S. adults who have peanut allergies developed them after age 18.
- They note that adults are less likely to receive a diagnosis with the condition because doctors aren’t on the lookout for this allergy in adults.
- They add that symptoms and treatments for adults with peanut allergies are similar to children with the condition.
Nearly 1 in 5 adults in the United States who have peanut allergies developed them after the age of 18, a new study from the Journal of Allergy and Clinical Immunology suggests.
This represents more than 800,000 adults, a surprising figure for an allergy typically thought to primarily present itself in children.
Adults were also less likely to be diagnosed than children were, perhaps because medical professionals are not as primed to look for peanut allergies in adults and adults are less likely to seek out doctors, the research suggests.
While no one knows exactly how adult-onset allergy to peanuts happens, there are theories, said Dr. Phil Lieberman, an allergist in Tennessee who is the chair of the American College of Allergy, Asthma and Immunology Food Allergy Committee.
“I suspect that the majority of the patients who had adult-onset food allergy had oral allergy syndrome,” Lieberman told Healthline. “It occurs when patients who are pollen allergic develop symptoms to fruits and nuts over time. This would be expected to cause patients to develop symptoms to peanuts in adulthood that were not there in childhood. This is supported by the fact that those responders with adult-onset food allergy were more likely to have environmental allergies than those with childhood-onset.”
Regardless, if you do suspect you might have a late-developing peanut allergy, it’s important to see an allergist.
“The study shows that there are many more adults who report having a peanut allergy than there are who are actually diagnosed by an allergist as having a peanut allergy,” said Dr. Katie Marks-Cogan, a pediatric and adult allergist in California and co-founder of Ready, Set, Food, a service that promotes early childhood allergen exposure. “Seeing a board-certified allergist is the best way to find out if you have a true peanut allergy, so I’d recommend seeing one if you have any symptoms when you eat peanuts.”
A problem for adults
In addition to highlighting that the prevalence of adult-onset peanut allergy is higher than previously thought, the study also points to the fact that most children don’t outgrow their peanut allergies, making it an ongoing adult problem.
“We know that around 80 percent of children with a food allergy will not outgrow their peanut allergy. There has been an overall increase in children with reported peanut allergy over the past 20 years, so seeing an increase in adults with food allergies makes sense as children with peanut allergy become adults with peanut allergy,” Sherry Coleman Collins, MS, RDN, a registered dietitian in Georgia and consultant to the National Peanut Board, told Healthline.
The other reason we are seeing increases in allergies can also be an increase in awareness of symptoms and prevalence.
“One reason we may see more reported food allergies in adults is that there is a greater awareness of food allergies,” Coleman said. “The study of food allergies is relatively new and there is much we do not understand.”
Prevention and treatment
Whether you develop peanut allergies in adulthood or carry them into adulthood, symptoms are likely to be similar as well as treatments.
That means seeing an allergist and getting an epinephrine prescription in the case of a severe allergic reaction.
People who develop this allergy in adulthood are less likely to have an epinephrine auto-injector. Only 44 percent of adults with adult-onset peanut allergy have an auto-injector compared to 56 percent of adults whose allergy developed in childhood, the study reported.
Beyond having protective epinephrine, new antibody treatments can help prevent life-threatening allergic episodes, research shows.
Finally, if peanut allergies run in your family, you might be able to prevent your children from developing peanut sensitivity by exposing them to the allergens early in life, even during the first few months of life, according to recommendations from the American Academy of Pediatrics.