Red Alert: Exclusive Breastfeeding Threatened

This is not a typical Editorial. It is neither a systematic review or meta-analysis of a particular subject, nor a focused discussion of a specific aspect of medical care. Simply put, it is a cry of concern from someone who has been dedicated for years to the advocacy and support of breastfeeding as the “normative standard of infant feeding and nutrition.” ¹

As such, the universal guidelines, be it from the World Health Organization, the American Academy of Pediatrics, or the Academy of Breastfeeding Medicine, have been exclusive breastfeeding for about 6 months, followed by continued breastfeeding while complementary foods are introduced.

But this is no longer. So what has changed? Apparently there is an increasing concern that food allergies are a major pediatric health problem, and in return there is a developing concept of “allergy prevention” based on the early introduction of specific allergens to the diet of the infant. The impetus to this change was the study documenting that the introduction of peanuts to the diet of infants who are at an increased risk of developing peanut allergy as early as age 4 months will significantly reduce the future development of allergic symptoms. While the study was limited to the beneficial effect in infants defined as high risk for peanut allergy, subsequently the European Academy of Allergy and Clinical Immunology updated and expanded their guidelines to recommend peanut exposure for all infants regardless of any risk factor. ²

This breach in the concept and value of breastfeeding exclusivity essentially “licensed” other investigators to explore potential allergy prevention benefits to other known allergens, (such as the feeding hens’ egg at 4 months that resulted in a reduction of egg allergy). ³ Despite this limited “success” of allergy prevention, however, it became clear to many that the more consequential public health consequence was that the “dam was broken” and exclusivity per se was no longer the absolute feeding recommendation, and that the 6-month goal of exclusivity was no longer the holy grail.

Not surprisingly, other investigators argued that waiting till 4 months to expose infants to cow’s milk protein was “missing the boat” and that exposure should be even earlier, especially if we are concerned about the major pediatric problem of cow’s milk allergy. Peters, ⁴ in a 2019 observational study reported that infants exposed to cow’s milk protein in the first 3 months of life had a lower incidence of cow’s milk allergy. In 2020, Sakihara and colleagues ⁵ reported the results of a prospective study wherein breastfeeding infants were randomized to ingest or not a minimal aliquot of formula from the age 1–2 months. The bottom line from this study was that an early (age 1–2 months) ingestion of 10 mL of cow's milk formula per day significantly reduced the subsequent development of cow’s milk allergy.

Further analysis of this Japanese study ⁶ noted the infants who were exposed to cow’s milk-based formula in the immediate postpartum period and then continued with solely exclusive breastfeeding as compared to those infants who were similarly exposed to formula in the first days after birth but continued to ingest: formula along with mothers’ milk had an increased rate of cow’s milk allergy. Simply put, even a minimal exposure to cow’s milk in the immediate postpartum period obligates continuing to feed some formula as the infant has been sensitized and needs the benefit of a continuous desensitizing exposure.

Lachover-Roth ⁷ in 2022 reported on a prospective nonrandomized study comparing infants who were exclusively breastfed and those who received any amount of cow’s milk formula from birth and noted that all the IgE-mediated cow’s milk allergy infants were in the exclusive breastfeeding group.

These seemingly confusing and, to a degree, counterintuitive results might well be explained by the report of Elizur ⁸ who documented that when mothers who reported that they exclusively breastfed their infants in the postpartum period in the hospital had a review of their hospital chart, in reality, 55% of the infants had received formula without their knowledge. This finding is matched to a degree by the recent U.S. Breastfeeding Report Card, which noted that 20% of infants receive formula in the first 2 days of life.

Despite significant methodological problems in these studies, as summarized by Huffaker, ⁹ a growing consensus among some allergists is that allergy prevention in the breastfeeding infant should be a more routine practice and based on two principles ¹⁰ : 1.

All infants should ingest daily, for 2 months, at least a small aliquot (10 mL) of cow’s milk formula beginning at 1 month of age.

As I noted, the quality of the data from the above-noted studies do not in my mind justify such categorical management pronouncements. But beyond a debate as to what degree these recommendations are evidence-based are two other overwhelming concerns. Feeding peanuts even as early as the 4th month does not conceptually suggest that we are providing an alternative to breast milk. In contrast, feeding cow’s milk-based formulas to an infant (even as little as 10 mL) as early as day 3 of life because he/she was fed formula at 3 AM while the mother was sleeping or let alone feeding an aliquot of formula routinely at 1 month will inevitably be interpreted by mothers that cow’s milk formula has been legitimated as a viable alternative feeding substance. And so will go exclusivity if not to a degree breastfeeding itself.

Yes, this is a RED ALERT and WAKE UP CALL for our global colleagues who share our concern for the well-being of the maternal-infant dyad. Clearly, well-meaning allergists should not be dictating from their narrow perspective infant feeding policies and protocols.