Summertime brings more opportunities for encounters with the tropical coconut, but there's long been confusion over whether this plant progeny can cause allergies in people.
The simple answer is yes, but rarely.
"Coconut allergy isn't something that comes up very often," Julie McNairn, MD, an allergist in private practice in Ithaca, New York, told Ƶ. "It's a very rare allergy."
A 2023 survey of nearly 79,000 people in the U.S. found a prevalence of about 0.39% for "convincing" coconut allergy. For comparison, about 2% of the population has a peanut allergy, McNairn said.
The survey found coconut allergy to be more prevalent among adults than children (0.43% vs 0.22%). Those numbers were even smaller when limited to those who had a diagnosis confirmed by a physician (0.2% of adults and 0.12% of children).
In addition, only about 40% of people with coconut allergy had a prescription for epinephrine to rescue them from anaphylaxis should they accidentally ingest coconut. The study authors wrote that this suggests "coconut allergy management practices remain suboptimal."
McNairn noted that since coconut oil can be used in topical products, there's also a potential risk of contact dermatitis with coconut as well.
The peculiar thing about coconut, she said, is that it's actually a fruit, not a tree nut. However, the , so it must be disclosed as such under food labeling laws.
In 2004, Congress passed the Food Allergen Labeling and Consumer Protection Act, which established : milk, eggs, fish, shellfish, tree nuts, peanuts, wheat, and soy. In 2021, the expanded the definition of major food allergens to include sesame, and product labeling was required for this allergen beginning in January 2023.
"'Tree nuts' is obviously a group of things, not a single thing like peanut or egg, but coconut gets grouped into that category," McNairn said, adding that labeling of 'tree nuts' isn't consistent. Sometimes, individual nuts like almonds, cashews, or hazelnuts are listed separately, while other times the general term is used.
It's not often that coconut is listed individually as an allergen on a food label, but it does sometimes happen, McNairn said.
"It's just something that manufacturers may be disclosing more," she added. "When sesame was added [to the list of major allergens], it's brought about a bit more change, but I'm not sure that had a ripple effect with coconut as well."
Christopher Warren, PhD, of Northwestern University in Chicago, who authored the coconut allergy prevalence study, noted at the time FALCPA was passed, there were "no solid data suggesting that coconut allergy was a big concern."
Nonetheless, it's still considered to be a tree nut "in the eyes of the law, so it has to be labeled when it's present in packaged goods."
But the problem with that is, it's not likely to pose a problem for most consumers -- even those with true tree nut allergy.
"If you're allergic to one type of fish, you're probably allergic to other types of fish because the proteins are similar," Warren said. "For tree nuts and coconut, there's not that same dynamic because they're not very close botanically. So maybe a lot of kids with tree nut allergy don't need to be avoiding coconut."