Picture this: You're standing in your kitchen; you've just filled the better part of a gorgeous cheese board. It's completely Instagram-worthy. The last fruit to add is the deliciously ripe mango you grabbed on a whim. You begin to peel it, and as you do, you notice that your hands tingle. Soon, they start to itch. It feels similar to the poison ivy rash you had last summer. Little did you know that the two are connected, and that if you've ever had poison ivy, you might be allergic to these things now, too. That in fact, there's a whole family of plants that might be off-limits.
Poison ivy and mangoes are both a part of a family of plants referred to as Anacardiaceae, which, according to The University of Hawaii, includes several other common trees such as cashews and pink peppercorns. They all contain the same irritating agent. I spoke with Dr. Purvi Parikh, allergist/immunologist with Allergy & Asthma Network, who said that "Both poison ivy and mango sap contain a chemical called urushiol, so that touching a mango in some people who are sensitive to poison ivy can cause a similar blistering rash," which is referred to as contact dermatitis.
Some people are particularly sensitive to this chemical, which is found in the leaves, bark, and skin of the fruits. The National Library of Medicine (NLM) noted that exposure to urushiol usually initiates contact dermatitis.
The good news is that according to Dr Parikh, most people who are allergic to urushiol can eat the flesh of the mango just fine, as it's only found in the skin and leaves. You just want to be careful when you handle it, especially if you've ever had poison ivy. It all has to do with exposure, and how getting one allergic reaction makes you more likely to have subsequent reactions. And it might take years of experience to make the connection: If you'd never cut your own mango before, you wouldn't know if it made you itchy. Or you might cut mangoes all the time, and know that you have to wear gloves to do it, but camping isn't your thing, so you've never had poison ivy. At least very few people in the United States have ever had cause to cut up a cashew apple, so it's not like anyone here is regularly getting cashew apple rashes. Still, being allergic and exposed to poison ivy or oak might make you more prone to develop the allergy based on exposure if you ever did find yourself harvesting cashews.
The NLM cited one specific case of tourists to Israel developing dermatitis after picking mangoes straight from the trees. They wrote, "American patients employed in mango picking at a summer camp in Israel, developed a rash of varying severity. All patients were either in contact with poison ivy/oak in the past or lived in areas where these plants are endemic. None recalled previous contact with mango." So they had no clue that they would be allergic.
They continued, "In contrast, none of their Israeli companions who had never been exposed to poison ivy/oak developed mango dermatitis. These observations suggest that individuals with known history of poison ivy/oak allergy, or those residing in area where these plants are common, may develop allergic contact dermatitis from mango on first exposure."
Wild, right? Allergies are weird and often unpredictable. The immune system spends all of its time fighting off foreign invaders, and protecting our bodies from themselves. However, sometimes there's a bit of a glitch, according to The Virtual Medical Center. Occasionally, the body will treat something harmless like peanuts or mango skin as an enemy invader, and will trigger immunoglobulin E (also known as igE) antibody production, which irritates the mast cells, subsequently releasing histamines and leukotrienes to attack. That causes the noticeable allergic reaction.
Unfortunately, with sensitization, the reaction is not always the same... and that makes it dangerous, according to The Academy of Allergy, Asthma, and Immunology. Dr. Parikh notes that "If you have history of contact dermatitis or blistering rash with poison ivy then you should be careful when handling mangoes, but do not need to see an allergist unless it is severe." Thank goodness, because those things are delicious.