Allergies Can Drive You Nuts

By Sally Squires
Tuesday, May 16, 2006


That's how a Lean Plate Club member from Maryland felt recently when a flight attendant asked passengers not to open any food that might contain nuts. The puzzle? The same airline had served nuts on the outgoing fight.


About whether a fellow passenger might eat nuts. "It would be quite devastating for me to, say, touch the airplane bathroom handle right after a passenger who has been eating almonds has left it," says a Lean Plate Club member who (mistakenly) fears that this alone could set off her almond allergy. "Same goes for armrests and tray tables."


"When I was a kid, it seemed like we all ate peanut butter like it was going out of style!" noted a 30-year-old Lean Plate Club member in a recent Web chat. "Now it is sometimes banned in day care centers and school cafeterias."


"I'm allergic to nuts," e-mailed a Lean Plate Club member recently. "Allergic as in throat swells up, [hospital] ER visit allergic. [But] even I can sit next to people eating nuts. . . . I have a feeling that some of the allergic people have gone overboard and need to get over it."

Well, maybe.

To clear the air, let's get some expert help from Hugh A. Sampson, director of the Jaffe Food Allergy Institute at Mount Sinai School of Medicine in New York and medical director of the nonprofit Food Allergy and Anaphylaxis Network's advisory board in Northern Virginia.

One percent . That's the proportion of Americans -- about 3 million people -- who are allergic to either peanuts (technically a legume, not a nut), tree nuts (such as almonds and walnuts) or both. Nut allergies account for the majority of the 30,000 severe food allergic reactions that occur annually, causing 2,000 hospitalizations and about 200 deaths. For 99 percent of the population, however, nuts are a good source of healthy fat that helps protect the heart.

It's not your imagination. If it seems like more attention is being paid to peanut and nut allergies, it's because the incidence is rising in the United States and other Western countries, for reasons that are not understood. Consumption alone doesn't explain it. In the United States and China, per-capita consumption of peanuts is the same, but China has virtually no peanut allergies. One difference: We eat mostly dry-roasted peanuts, even in peanut butter; the Chinese eat peanuts either boiled or fried. The higher temperatures from dry roasting appear to expose more allergens in the peanuts, Sampson says.

Fear of flying . In 1999, Sampson and his colleagues investigated 62 suspected allergic reactions to nuts among airline passengers. They verified 42 cases. Half occurred in children aged 2 or younger who either ate airline food containing nuts or found stray nuts on the plane. There were no deaths, although 19 people required treatment in flight to ease breathing problems. Another 14 were treated after landing. Eating nuts caused the most severe reactions, followed by inhalation of nut dust and exposure on the skin.

Best time to fly if you have nut allergies: early morning, when planes are cleanest. Bring your own food, and if you're really worried, wear a surgical mask, Sampson says, although he notes that many people with nut allergies fly and never have a problem.

Hand washing. Aside from avoiding food with nuts, washing is one of the best protections against allergic exposure, Sampson says. That's because many people, especially children, put their hands in their mouths frequently. No soap and water available? Carry pre-moistened towels to wipe hands and easily reached surfaces. The good news: Skin exposure alone rarely produces more than annoying rashes or hives.

Age advantage . About 20 percent of children who are allergic to peanuts outgrow the allergy -- a far better outlook than researchers believed just a decade ago. But that's still small compared with the estimated 80 percent who outgrow allergies to other foods, including wheat and soy.

Reduce risk. Most American children are exposed to peanuts in the first year of life either through food or breast milk, or in utero when their mothers eat peanut products. In countries where peanut butter consumption is low, peanut allergies are also much less common. In the United Kingdom, the National Health Service advises women from families with peanut allergies to avoid eating peanut products during pregnancy and while nursing, and to wait until their children turn 3 before introducing peanut products. ยท

Join Sally Squires, author of the newly published "Secrets of the Lean Plate Club" (St. Martin's Press), online from 1 p.m. to 2 p.m. Tuesdays at, where you can also subscribe to the free LPC e-mail newsletter.

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