I have praised Marty Makary’s Blind Spots in earlier posts, partly for its compelling examples of where mainstream medicine has failed to adapt to new, strong, sometimes observational evidence. His opening major example is the American Academy of Pediatrics’s long ban on giving peanuts to infants and toddlers. Instead of protecting them from peanut allergy, the ban caused a large increase in peanut allergy. In the essay quoted below, Makary summarizes the peanut example from Blind Spots.
(p. C4) In 1999, researchers at Mount Sinai Hospital estimated the incidence of peanut allergies in children to be 0.6%. But starting in the year 2000, the prevalence began to surge. Doctors began to notice that more children affected had severe allergies.
What had changed wasn’t peanuts but the advice doctors gave to parents about them. The American Academy of Pediatrics (AAP) wanted to respond to public concern by telling parents what they should do to protect their kids from peanut allergies. There was just one problem: Doctors didn’t actually know what precautions, if any, parents should take. Rather than admit that, in the year 2000 the AAP issued a recommendation for children 0 to 3 years old and pregnant and lactating mothers to avoid all peanuts.
. . .
Dr. Gideon Lack, a pediatric allergist and immunologist in London, had a different view. In 2000 he was giving a lecture in Israel on allergies and asked the roughly 200 pediatricians in the audience, “How many of you are seeing kids with a peanut allergy?” Only two or three raised their hands. Back in London, nearly every pediatrician had raised their hand to the same question.
Startled by the discrepancy, he had a eureka moment. Many Israeli infants are fed a peanut-based food called Bamba. To Lack, this was no coincidence, and he quickly assembled researchers in Tel Aviv and Jerusalem to launch a formal study. It found that Jewish children in Israel had one-tenth the rate of peanut allergies compared with Jewish children in the U.K., suggesting that genetic predisposition was not responsible, as the medical establishment had assumed.
Lack and his Israeli colleagues titled their paper “Early Consumption of Peanuts in Infancy Is Associated with a Low Prevalence of Peanut Allergy.” However, the 2008 publication was not enough to uproot groupthink. Avoiding peanuts had been the correct answer on medical school tests and board exams, which were written and administered by the American Board of Pediatrics. For nearly a decade after AAP’s peanut avoidance recommendation, neither the National Institute of Allergy and Infectious Diseases (NIAID) nor other institutions would fund a robust study to evaluate whether the policy was helping or hurting children.
Meanwhile, the more that health officials implored parents to follow the recommendation, the worse peanut allergies got. From 2005 to 2014, the number of children going to the emergency department because of peanut allergies tripled in the U.S. By 2019, a report estimated that 1 in every 18 American children had a peanut allergy. . . .
In a second clinical trial, published in the New England Journal of Medicine in 2015, Lack compared one group of infants who were exposed to peanut butter at 4-11 months of age to another group that had no peanut exposure. He found that early exposure resulted in an 86% reduction in peanut allergies by the time the child reached age 5 compared with children who followed the AAP recommendation.
. . .
When modern medicine issues recommendations based on good scientific studies, it shines. Conversely, when doctors rule by opinion and edict, we have an embarrassing track record. Unfortunately, medical dogma may be more prevalent today than in the past because intolerance for different opinions is on the rise, in medicine as throughout society.
For the full essay see:
(Note: the online version of the essay has the date September 19, 2024, and has the title “How Pediatricians Created the Peanut Allergy Epidemic.”)
Makary’s essay is adapted from his book:
Makary, Marty. Blind Spots: When Medicine Gets It Wrong, and What It Means for Our Health. New York: Bloomsbury Publishing, 2024.