An understanding of immigrant parents’ backgrounds helped reveal the distinct biocultural context in Mexico that shaped their feeding practices and their conceptions of oral disease and its causes. The majority of caregivers came from the classic sending states in western and central Mexico—Michoacán, Jalisco, Zacatecas, and Guanajuato. Rural communities in central and western Mexico have long been linked to the Central Valley through migration networks, yet such routes were institutionalized during the Bracero Program of 1942–64. During this period the United States imported 4.6 million Mexican laborers—many of them small landholders and peasants—to work as temporary “guestworkers” in agriculture and the railroads (Ngai 2004
). In short, migration networks from rural parts of western and central Mexico generally provide the supply of farm laborers to feed the demands of California agribusiness. Thus, all but four of the Mexican caregivers the first author interviewed were from small rural towns they termed ranchos
—towns of 15,000 people or less. Because of their rural origins and recent arrival, they were less familiar with U.S. biomedical understandings of the causes of oral disease and its proper treatment.6
Caregivers’ oral health experiences were shaped by the environments in which they were raised in Mexico—environments that contrasted sharply with those their children faced in the United States. An examination of the diets and infant feeding practices caregivers described as being common to rural Mexico illustrates the biocultural transition they underwent on arriving in the United States. All but two of 26 caregivers had grown up on family farms in which their diets depended on subsistence agriculture. Only one caregiver—whose family was wealthier than the others—described her diet as having been high in processed and refined foods because her family owned a small store. Yet the relatively uncariogenic diet of rural Mexico strongly contrasted with the diet they encountered on arrival in the United States—one in which sodas, candies, and processed and refined foods were the norm.
On arrival in the United States, immigrant caregivers’ socioeconomic circumstances as well as federal policy shaped a dramatic change in infant feeding practices. The structure of farmwork, combined with federal policies that make infant formula affordable, encouraged a shift from breast-feeding to bottle-feeding. Because it is low-paid work, few farmworking families can survive without mothers themselves entering the workforce. Immigrant mothers found themselves newly navigating a contradiction between the task of farmwork and that of mothering (see de la Torre 1993
). Although their own mothers had helped out at family farms in rural Mexico, the rhythms of industrial farmwork in the United States do not accommodate childcare. None of the women we interviewed simultaneously worked in the field and breast-fed their children. In fact, women reported that the amount of time they breast-fed their children was directly shaped by the seasonal schedule of farmwork. Most women worked during the lucrative summer harvest season and rested during the winter. Thus, a child born directly after the harvest season might be breast-fed for six months, whereas one born in the late spring or summer might not be breast-fed at all. In short, the structure of farmwork demanded that working mothers bottle-feed their children; breast-feeding was a luxury few farmworking mothers could afford.
If farmwork itself makes bottle-feeding incumbent, federal policies through WIC abet this transition from breast-feeding to bottle-feeding. The cost of infant formula in Mexico had made it a luxury few peasant families could afford, yet WIC coupons make infant formula affordable. Farmworking mothers often described WIC coupons for infant formula as una gran ayuda (a great help). Indeed, one mother from urban Colima had explained that she was forced to bottle-feed her two eldest children in Mexico with infant formula when her “milk dried up.” This was a great hardship for her family; she paid $18 each week—nearly half her husband’s weekly income—on infant formula for her two children. Her own mother had tried “everything she could” to encourage this woman’s milk to flow—including remedios caseros (home remedies) such as rubbing her back with hot oils—“but nothing worked,” she said. In the United States, in contrast, WIC coupons made infant formula readily accessible at low cost. Given the need for women to work, and the cheap cost of formula, the economic calculus of infant feeding had flipped on its head—in the United States, breast-feeding, rather than bottle-feeding, became more costly.
A quick glance at the numbers helps illustrate how pronounced this transition was for immigrant caregivers. Fourteen of the 26 caregivers we interviewed reported that they had bottle-fed their U.S.-born children alone; an additional nine had combined breast-feeding with bottle-feeding. Those caregivers who did combine breast-feeding with bottle-feeding did so for only a brief period of time—the average time a child was breast-fed was seven months. Only four of the 55 U.S.-born children in our sample were breast-fed alone. Yet immigrant women themselves had predominantly been breast-fed when they were children—partly because of custom and partly because of the high expense of formula. Only two of our 26 immigrant caregivers reported having been predominantly bottle-fed because of exceptional circumstances—because their mothers “could not breast-feed.”
Moreover, the majority of the caregivers in our sample had bottle-fed their children until late—until two or three years of age. A mix of structural and cultural circumstances help explain this practice. As immigrant caregivers understood it, the bottle—a substitute for their breast—had come to stand in for mothering. Once children had grown accustomed to bottle-feeding, immigrant mothers found it difficult to prize the bottle from their hands. Although WIC urged mothers to wean their children by the age of one, mothers said they often grew tired of luchando (struggling) with their children. Many immigrant mothers gave the bottle to their children as a comfort during daycare or when they put them to sleep at night.
Because immigrant mothers were first-generation bottle-feeders, they were unprepared for the oral health consequences of prolonged bottle-feeding. Studies have linked the consumption of sugary liquids in bottles for prolonged periods of time to “Baby Bottle Tooth Decay”—or the decay of the front upper teeth (Shiboski et al. 2003
). Unaware of such consequences, some immigrant caregivers placed juice or Nesquik®-flavored milk in bottles and allowed their children to feed at night. The structure of farmwork and the availability of infant formula had encouraged immigrant caregivers to abandon breast-feeding in favor of bottle-feeding. Yet because they were unaccustomed to the oral hygiene requirements of the new cariogenic environment they found in the United States, their adoption of appropriate health behaviors lagged behind their adoption of new infant feeding practices.
The experiences of Lupita, a mother from La Cañada, Michoacán, serve to illustrate this biocultural transition. Lupita grew up on a family farm where her family regularly consumed the corn, garbanzos, wheat, and lentils they themselves grew. Because of her family’s poor peasant origins, sweets and sodas were a luxury. She remembers that her younger brother was breast-fed until age three; she assumes she was as well. “Because what other way could it be?” she asks. Formula, she says, was too expensive. Yet on migrating to the United States, her entry into farm work made breast-feeding more difficult. When she had her first child in March, she switched him to infant formula after two months so she could work during the lucrative harvest season. “We have to leave at four in the morning, and get home at four in the afternoon. For that reason there’s the problem that here kids drink more bottle than mother’s milk,” she says. Her son drank from the bottle until he was three. Unaware of its detrimental impact on teeth, she sometimes put him to bed with Nesquik®-sweetened milk.
Lupita’s experiences illustrate the pronounced biocultural transition parents from rural Mexico experience as they arrive in a markedly different environment in the United States. Although families’ socioeconomic needs required that women abandon breast-feeding in favor of bottle-feeding, immigrant mothers were unfamiliar with the oral hygiene requirements of this new infant feeding practice. They had adopted bottle-feeding in a markedly new environment—one of plentiful access to formula and low-cost sugary drinks. If we return to the opening story of Raquel’s successive dental misfortunes, we can understand how Margarita’s adjustment to her new life in the United States helped mediate her daughter’s early childhood caries. Accustomed to the relatively less cariogenic diet and infant feeding practices of rural Mexico, immigrant caregivers’ oral hygiene practices had not adapted as quickly to their new circumstances.