Breast or Bottle?: Contemporary Controversies in Infant-Feeding Policy and Practice

2. From “Wives’ Tales and Folklore” to Scientific Fact: Rhetorics of Breastfeeding and Immunity in the Mid–Twentieth Century

32 2 From “Wives’ Tales and Folklore” to Scientific Fact Rhetorics of Breastfeeding and Immunity in the Mid-Twentieth Century The idea that human milk affords the nursing infant a unique form of immune protection is not new. In fact, an immunology article published in 1988 cites an 1892 German study as the first to report that human milk affords some kind of immune protection.1 A pediatrics article published in 1974 cites studies dated 1922, 1934, 1935, 1958, and 1961, all of which reported clinical results suggesting that breastfed babies fared better immunologically than their bottle-fed peers.2 Despite this apparent cause-effect relationship, however , throughout much of the twentieth century the notion that breastfeeding might provide immune protection was perceived as mere speculation rather than scientific fact. As the introduction to a 1979 book entitled Immunology of Breast Milk explained, “both medical and veterinary scientists have long recognized the potential importance of immunity acquired after birth from the mother, although in clinical practice the arguments have often been accused of being wives’ tales and folklore.”3 In today’s medical discourse, it appears that this old idea about human milk’s immune protection has finally found its time—we might say it is the right kairotic moment for beliefs about human milk’s immune protection to be accepted as scientific fact. For instance, the AAP’s 1997 policy statement cites numerous studies to support the claim that breastfeeding protects against childhood diseases, including “diarrhea, lower respiratory infection, otitis media, From “Wives’ Tales and Folklore” to Scientific Fact 33 bacteremia, bacterial meningitis, botulism, urinary tract infection, and necrotizing enterocolitis.” The statement also cites studies that “show a possible protective effect” against several adult diseases, many of which are currently understood as related to the immune system, including “insulin-dependent diabetes mellitus, Crohn’s disease, ulcerative colitis, lymphoma, allergic diseases , and other chronic digestive diseases.”4 The AAP’s revised 2005 statement uses more definitive language and includes a longer list of infectious diseases than the 1997 statement. Specifically, the 2005 statement says: “Research in developed and developing countries of the world, including middle-class populations in developed countries, provides strong evidence that human milk feeding decreases the incidence and/or severity of a wide range of infectious diseases including bacterial meningitis, bacteremia, diarrhea, respiratory tract infection, necrotizing enterocolitis, otitis media, urinary tract infection, and late-onset sepsis in preterm infants.”5 Like the 1997 statement, the 2005 statement cites numerous scientific studies to support each of these claims. Although both AAP policy statements cite a great deal of scientific evidence , the significant shift in medical beliefs that has occurred from the mid– twentieth century to the present has had little to do with scientific discoveries of new evidence about human milk’s immune-protective properties. Rather, this shift in beliefs has occurred because a change in the metaphor that governs understandings of human immunity has produced a kairotic moment that is more amenable to scientific arguments in favor of human milk’s immune protection. There has not been a particular scientific breakthrough or event that suddenly produced evidence so convincing that it definitively answered the long-standing question of whether or not human milk offers the infant immune protection. What has occurred is a more fundamental transformation in expert consensus about the essence of the object being studied, and that transformation has been possible because of a shift in the metaphor that shapes popular and scientific conceptions of human immunity. To explore the rhetorical dimensions of this transformation, it is important to examine the scientific arguments about infant feeding and immunity that unfolded in key medical journals in the last half of the twentieth century. Our rhetorical analysis is based on close examination of fifty-nine articles from a wide range of pediatrics and immunology journals. To select these articles, I started by locating the key texts on infant feeding and immunity that the 1997 and 2005 AAP policy statements cite to justify their claims about the immune benefits of breastfeeding. From there, I worked backwards, attempting to locate any text cited as making a groundbreaking claim about infant feeding and immunity. Although research has led me to encounter a few publications that are much older, the majority of the articles were published from 1940 to 2005. 34 Breast or Bottle? Closely examining the rhetorical transformation in beliefs about infant feeding and immunity that has occurred...