In the decade between 2006 and 2016, prescriptions in the U.K. for infant formula for babies with cow's milk allergy rose sixfold, resulting in a sevenfold increase in National Health Service spending on nondairy specialty formulas, yet there's no evidence that the true prevalence of the condition has increased.
So, what's going on? Why are pediatricians recommending nondairy formulas at such an increased rate if there's no need? According to a recent paper1 by Chris van Tulleken, Ph.D., honorary senior lecturer at University College London, the discrepancy appears to be driven by makers of infant formula.
"Allergy to cow's milk protein may be acting as a Trojan horse for the $50 billion (£40billion; €44billion) global formula industry to forge relationships with health care professionals in the U.K. and around the world," Tulleken writes.2
"Experts believe these relationships are harmful to the health of mothers and their children, creating a network of conflicted individuals and institutions that has wide ranging effects on research, policy and guidelines. Potential overdiagnosis of the allergy can also have negative effects on breastfeeding."
Milk Allergy Prevalence Has Remained Steady for Past Decade
I've written numerous articles about the influence of funding, and this appears to be a powerful example of what happens when you allow industry to pay for the creation of medical guidelines. According to Tulleken, there's no evidence showing that milk protein allergy has become more common. In fact, studies published in 20073 and 20164 reveal no significant rise in prevalence.
• In 2007, research estimates of cow's milk protein allergy ranged from 2 to 7.5 percent. According to the authors, "Differences in diagnostic criteria and study design contribute to the wide range of prevalence estimates and underline the importance of an accurate diagnosis ..."
• By 2016, incidence of cow's milk protein allergy was estimated to be between 5 and 7 percent in formula-fed babies, and 0.5 to 1 percent in breastfed babies.
At this time, the authors warned that widespread confusion about the differences between lactose intolerance and milk allergy among physicians was a problem that "could result in unnecessary dietary restriction."
As explained in this paper, "The currently accepted nomenclature is determined by the mechanism likely to be producing the symptoms, with cow's milk allergy being immune mediated and lactose intolerance not immune mediated. An infant with suspected IgE-mediated milk allergy will require testing for specific IgE to milk (skin prick test or blood tests)."
Guidelines Funded by Formula Makers Have Led to Overdiagnosis of Milk Allergy
According to Tulleken, overprescription of nondairy formula appears to be the result of industry funding the guidelines used to diagnose dairy allergy. He also warns that formula makers place undue emphasis on the need to stop breastfeeding as part of the diagnostic strategy.
Between 2007 and 2017, six milk allergy guidelines were published. On two occasions, the guidelines were directly funded by infant formula makers. The remaining four guidelines had contributing authors who had received funding from formula makers.
The end result is guidelines that are so vague they could apply to all children. For example, the symptoms listed in Allergy UK's guidelines5 are so broad and universal that milk allergy can easily be diagnosed in completely healthy babies.
As noted by Dr. Gary Marlowe, vice chair of City and Hackney Clinical Commissioning Group,6 "Virtually every single infant could potentially be diagnosed using these symptoms." Formula makers also influence prescribing behaviors through sponsored education.
While organizations responsible for educating patients and medical professionals about milk protein allergy appear independent, most in fact receive funding from formula makers. In the U.K., these include Allergy UK, the Allergy Academy and the British Society for Allergy and Clinical Immunology (a professional society of allergists). As reported by Inverse:7
"According to the World Health Organization's International Code of Marketing of Breast-milk Substitutes,8 published in 1981, companies that make milk substitutes are not supposed to directly educate mothers, create conflicts of interest or advertise through health systems.
But based on the information van Tulleken presents, it seems that infant formula manufacturers are finding ways to exert a strong influence on how doctors diagnose and treat patients.
'I obviously work within a high-tech medical system, but I see firsthand that we need to be really aware of the harm we can do and the immense influence industry has over our profession,' van Tulleken tells Inverse. 'No one is more vulnerable than a breastfeeding infant and their parent to industry exploitation' …
[S]ince the only way to confirm a non-IgE cow's milk protein allergy is for a baby to completely switch to a substitute before retesting their tolerance, the baby formula industry benefits from creating and sponsoring guidelines that are more generous in the use of milk substitutes.
In the service of these guidelines, the industry overstates the importance of stopping breastfeeding during this process.
'The basic research that provides the evidence that an infant can get a serious allergy through allergens in breastmilk is really, really weak,' says van Tulleken. 'We have a profusion of guidelines and educational programs for patients and doctors with so little investment in understanding the science of what is going on.'"