Five years ago, at a San Francisco elementary school, a nurse stood by to ensure that the children scrubbed their hands as they arrived, while their packed lunches were confiscated and searched for nut products. The measures were a precaution to protect a 5-year-old boy at the school who had a severe nut allergy.
In 2006 a town in Connecticut felled three hickory trees more than 60 feet high after a resident learned that the trees leaning over her property produced nuts and complained that they posed a threat to her grandson, who had nut allergies.
Recently, a Massachusetts school district evacuated a school bus full of 10-year-olds after a stray peanut was found on the floor.
Do these safeguards seem a little, well, nuts? Harvard professor Dr. Nicholas Christakis thinks so. One of Christakis' children attends school in the district that ordered the bus evacuation, and the episode prompted the physician and social scientist — best known for his work on the social "contagiousness" of characteristics such as obesity and happiness — to write a commentary, published in the British Medical Journal, questioning whether these so-called precautions are snowballing into something more like a societal hysteria.
Of the roughly 3.3 million Americans who have nut allergies, about 150 die from allergy-related causes each year, notes Christakis. Compare those figures with the 100 people who are killed yearly by lightning, the 45,000 who die in car crashes and the 1,300 who are killed in gun accidents. As a society, Christakis says, our priorities have become seriously skewed, and it's largely a result of fear. "My interest is in understanding [the reaction to nut allergies] as a spread of anxiety," he says.
Between 1997 and 2007, the number of children under 18 who suffered from food allergies jumped 17%, according to the Centers for Disease Control and Prevention. Experts don't disagree that the incidence of food allergies has increased, but there isn't much consensus as to why. Some researchers suggest that an overly hygienic lifestyle may hamper the body's ability to build up proper immunities; others believe the statistical rise is a combination of a real increase in allergies and an increase in the number of patients seeking diagnosis (i.e., getting allergy tests that turn up very low levels of reaction that might otherwise have gone undiscovered). "You have to distinguish between an epidemic of diagnoses and an epidemic of allergies," says Christakis.
No one would disagree that children who suffer from life-threatening allergies need to be protected, but the growing trend of demonizing nuts only fuels anxiety, Christakis says. Instilling in the general public the idea that nuts are a "clear and present danger" does little beyond heightening panic. "There are kids with severe allergies, and they need to be taken seriously," he says, "but the problem with a disproportionate response is that it feeds the epidemic."
There's even some evidence to suggest that establishing nut-free zones or nut-free schools may be detrimental to children's health, and increases their risk of developing nut allergies. A study cited by Christakis in his article revealed that, of 86,000 Jewish children living in the U.K. and Israel, those who had more exposure to peanuts earlier in life were less likely to become allergic later on. In the U.K., where peanuts are an infrequent part of the diet, nearly 2% of the children studied developed allergies; in Israel, where peanuts are a common part of the diet, from infancy onward, only 0.17% of children had a nut allergy.
But Dr. Robert Wood, chief of the Pediatric Allergy and Immunology department at Johns Hopkins Children's Center, cautions against putting too much stock in such epidemiological studies. "The reality is that the vast majority of kids — 95% plus — have no potential to get peanut allergies no matter what you do," he says, "and there's ½ % to 1%