How Experts Created a Peanut Allergy Epidemic

In the 25 years since the the American Academy of Pediatrics issued its peanut avoidance recommendation without compelling scientific evidence, the US has experienced an explosion of food allergies.

In 1992, with the help of a grant from the National Institutes of Health, The New England Journal of Medicine published a report on a rare phenomenon: fatal or near-fatal anaphylactic reactions in young people due to food allergies. 

Examining a period of 14 months, researchers identified thirteen cases, twelve of which involved asthmatic youths. Six of the thirteen anaphylactic reactions resulted in death, and each case had involved a young person with a known food allergy who had unknowingly ingested the food. 

“The reactions were to peanuts (four patients), nuts (six patients), eggs (one patient), and milk (two patients), all of which were contained in foods such as candy, cookies, and pastry,” researchers wrote. 

The paper said nothing about banning these foods, but concluded that “failure to recognize the severity of these reactions and to administer epinephrine promptly increases the risk of a fatal outcome.”

Nevertheless, food bans followed, and the Centers for Disease Control and Prevention (CDC) began to encourage educators to “consider possible food allergies” during food preparation. 

By 1998, the New York Times was reporting on the rise of peanut allergies and the measures school districts were taking to stop them. 

“Prodded by parents warning of lethal allergies, by the contentions of some researchers that peanut allergies are on the rise and, not least, by a fear of litigation, growing numbers of public and private schools across the country, including many of New York City’s most selective independent schools, have banned peanut butter from their cafeterias,” wrote Anemona Maria Hartocollis.

‘The Biggest Misconception’

When the Times published its article in 1998, the American Academy of Pediatrics (AAP) was not yet issuing recommendations about peanuts or food allergies in infants. But as public concern grew, they decided they had to offer guidelines of some kind. 

“There was just one problem,” Marty Makary, a Johns Hopkins University surgeon, noted in a recent Wall Street Journal op-ed. “Doctors didn’t actually know what precautions, if any, parents should take.”

Instead of remaining mum, the AAP followed the lead of the United Kingdom’s Committee on Toxicology and recommended that mothers avoid peanuts during pregnancy and lactation, and that children avoid peanuts until the age of 3.

The decision to make such a sweeping decision in the absence of compelling scientific evidence was a mistake, allergists say, and runs counter to basic immunology. 

Dr. Gideon Lack, an allergist at King’s College London, says the collective effort to cocoon children from peanuts and other foods is responsible for what has been described as a “food allergy epidemic.” 

The data suggest Lack is right. 

In the 25 years since the AAP issued its recommendation, the US (like the UK, which also advised peanut avoidance) has experienced an explosion of food allergies, especially peanut allergies. Data from Mount Sinai Hospital System in New York show that peanut allergies more than tripled in the decade and a half following the AAP’s guidance. In 1997, peanut allergies affected 1 in 250 children in the United States. By 2002, this rate had risen to 1 in 125, and by 2008, it reached 1 in 70 children. 

In 2016, Makary says, a single Missouri school district reported nearly a thousand students with life-threatening food allergies, primarily peanuts. He said the prevalence of the allergies prompted confusion from some of his international Johns Hopkins medical students. 

“What’s going on here?” one asked. “We have no peanut allergies in Africa.” 

“In Egypt, where my family is from, we don’t have peanut allergies either,” Makary answered. “Welcome to America.”

The anecdote would be amusing if the consequences of peanut allergies were not so serious. Data show that the number of emergency room visits for food-induced anaphylaxis increased nearly 1,000 percent nationwide in the wake of the AAP’s peanut avoidance guidance. 

Lack, who in 2008 co-authored a paper on the benefits of peanut consumption in infants, says there was never a good medical reason for health officials to urge pregnant mothers to avoid healthy foods.  

“The biggest misconception, specifically about food allergies, is that we will protect our babies and children against developing allergies by avoiding those foods in their diet, providing a sort of immunological cocoon where they’re not exposed to these dangerous foods out there,” Lack said in a recent interview. “This is just wrong.”

The Pretense of Knowledge

The AAP rescinded its policy in 2008, conceding that its recommendations were based on little evidence. Today, it’s once again considered safe for pregnant mothers to eat peanuts and pediatricians encourage introducing peanuts to infants as early as 6 months. 

Despite the guidance the AAP offered parents, a 2015 randomized study in The New England Journal of Medicine found early introduction of peanuts in infants “significantly decreased” the likelihood of children developing peanut allergies later in life.  

Yet the consequences of the bad recommendations were severe. More than 6 million Americans today have peanut allergies, according to recent estimates, and approximately 200,000 people land in the emergency room every year due to an anaphylactic reaction to a food allergy.

Makary says there’s a clear lesson public health officials can glean from the peanut allergy panic. 

“When modern medicine issues recommendations based on good scientific studies, it shines,” he writes. “Conversely, when doctors rule by opinion and edict, we have an embarrassing track record.”

The AAP didn’t start the peanut allergy panic, of course. The association was responding to it; but it was doing so with what the economist F.A. Hayek would call the “pretense of knowledge.” 

In his Nobel Prize acceptance speech, Hayek noted that humans, both individuals and planners, make countless decisions each day with “imperfect knowledge.” But he pointed out that even imperfect knowledge was preferable to “a pretence of exact knowledge.” Hayek warned that acting with a false sense of knowledge could have potentially “grave consequences,” especially when this knowledge was wielded by experts who see their plans as scientific and beyond reproach.

This is precisely what medical experts and public health officials did in response to the peanut allergy panic in the 1990s. Rather than admit that they didn’t know what precautions parents should take to keep their children safe from food allergies, they issued guidelines that harmed the immunological defenses of tens of millions of children. In doing so, they turned a small problem into the  full-blown food allergy epidemic that still exists today.

Why the peanut allergy epidemic continues to get worse each year, even though we now know that peanut avoidance in infants is unhealthy, is a difficult question to answer, but it might stem from a reluctance by the medical establishment to accept blame for the food allergy epidemic. 

Nearly a decade after the AAP rescinded its guidelines on peanut avoidance, the Mayo Clinic was asked about the mysterious surge in peanut allergies.

“Why is it that so many kids these days have peanut allergies?” the reader asked. “I don’t remember it being an issue even 20 years ago.”

“The reasons behind this dramatic increase are unclear,” the Mayo Clinic responded. “Lifestyle, diet choices and genetics all seem to play a role.”

Not a single word was mentioned about AAP’s recommendation that expecting mothers and infants should avoid eating peanuts at exactly the time their immunological defenses are developing.