Economist Writing Every Day

A headline, “How Pediatricians Caused the Peanut Allergy Epidemic” got me to click the other day. The article makes some important points, I think.

Having a peanut allergy is a serious health concern, both as an adult and for one’s child. For a sensitized person, exposure to peanut-containing products can be fatal if an Epi-pen or emergency room is not available for an epinephrin injection. Since this is an economics blog, I’ll note that a 2012 survey estimated the economic cost of any food allergy in US children at $24.8 billion annually, or $4184 per child. This includes direct medical costs, and the indirect costs, including opportunity costs, for children and their caregivers.

Out of an abundance of caution, pediatricians in the 1990s started recommending that parents keep peanuts from their infants and children. Instead of protecting children, however, this policy has done just the opposite. The incidence of peanut allergies has soared, with now some 2.5% of the pediatric population showing peanut allergies:

Around the year 2000 peanut allergies began to skyrocket. Sales of EpiPens, used in cases of peanut-induced anaphylactic shock, became a major expense for parents and a growing profit center for the manufacturer. … So, what changed? How did peanuts go from cheap, nutritious food source to become the little death pills that we think of them today? The answer is not what you would expect: pediatricians created the peanut allergy epidemic.

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. 

It did not have to go like this.  I poked about the web and found another article, titled The Medical Establishment Closes Ranks, and Patients Feel the Effects, which framed matters in terms of physician behaviors:

 Peanut allergies in American children more than tripled between 1997 and 2008, after doctors told pregnant and lactating women to avoid eating peanuts and parents to avoid feeding them to children under 3. This was based on guidance issued by the American Academy of Pediatrics in 2000.

You probably also know that this guidance, following similar guidance in Britain, turned out to be entirely wrong and, in fact, avoiding peanuts caused many of those allergies in the first place.

That should not have been surprising, because the advice violated a basic principle of immunology: Early exposure to foreign molecules builds resistance. In Israel, where babies are regularly fed peanuts, peanut allergies are rare. Moreover, at least one of the studies on which the British advice was based showed the opposite of what the guidance specified.

As early as 1998, Gideon Lack, a British pediatric allergist and immunologist, challenged the guidelines, saying they were “not evidence-based.” But for years, many doctors dismissed Dr. Lack’s findings, even calling his studies that introduced peanut butter early to babies unethical.

When I first reported on peanut allergies in 2006, doctors expressed a wide range of theories, at the same time that the “hygiene hypothesis,” which holds that overly sterile environments can trigger allergic responses, was gaining traction. Still, the guidance I got from my pediatrician when my second child was born that same year was firmly “no peanuts.”

It wasn’t until 2008, when Lack and his colleagues published a study showing that babies who ate peanuts were less likely to have allergies, that the A.A.P. issued a report, acknowledging there was a “lack of evidence” for its advice regarding pregnant women. But it stopped short of telling parents to feed babies peanuts as a means of prevention. Finally, in 2017, following yet another definitive study by Lack, the A.A.P. fully reversed its early position, now telling parents to feed their children peanuts early.

But by then, thousands of parents who conscientiously did what medical authorities told them to do had effectively given their children peanut allergies.

This avoidable tragedy is one of several episodes of medical authorities sticking to erroneous positions despite countervailing evidence that Marty Makary, a surgeon and professor at Johns Hopkins School of Medicine, examines in his new book, “Blind Spots: When Medicine Gets It Wrong, and What It Means for our Health.”

Rather than remaining open to dissent, Makary writes, the medical profession frequently closes ranks, leaning toward established practice, consensus and groupthink.

This article describes further instances of poorly-founded medical advice. Women were scared away from helpful estrogen hormone replacement therapy for many years because of unfounded fears of breast cancer. Blood donor institutions suppressed concerns about AIDS in donated blood, in order to not rock the boat:

In 1983, near the beginning of the AIDS crisis, the American Red Cross, the American Association of Blood Banks and the Council of Community Blood Centers rejected a recommendation by a high-ranking C.D.C. expert to restrict donations from people at high risk for AIDS. Instead, they issued a joint statement insisting that “there is no absolute evidence that AIDS is transmitted by blood or blood products.” The overriding concern was that Americans would not trust the blood supply, or donate blood, if people questioned its safety.

As with the advice on peanuts, a reversal came about far later than it should have. It took years for the blood banking industry to begin screening donors and it wasn’t until 1988 that the F.D.A. required all blood banks to test for H.I.V. antibodies. In the interim, half of American hemophiliacs, and many others, were infected with H.I.V. by blood transfusions, leading to more than 4,000 deaths.

That is poignant for me, since a good friend of mine died from AIDS that he contracted through a blood transfusion in that timeframe.

Well, what to do now about peanuts? It seems an obvious action is to expose infants to peanuts, at 4-6 months, along with other solid foods – – perhaps with the caveat to start with small doses and preferably stay within driving distance of an emergency room should that be needed. As for children who now manifest peanut allergies, there is some hope of desensitizing them if you start young enough, preferably no more than three years old.