In the present study, the relation between mothers’ and daughters’ relative weights was significant and of the same magnitude as that reported in family studies of obesity that included parents and young children (2
). This modest relation between the parent’s and child’s relative weights has been one of the critical pieces of evidence used in establishing familial patterns of adiposity (4
). The model shown in illustrates 2 paths that influence daughters’ relative weight: 1
) the direct path between mothers’ and daughters’ relative weights, which reflects both genetic and shared environmental effects; and 2
) a second path that depicts an environmental influence, maternal control in feeding, on daughters’ eating and relative weight. The full family-environment model provided a substantially better fit to the data than did the simple path model that evaluated only mothers’ BMI as a predictor of daughters’ relative weight. Moreover, although the path coefficients that reflect environmental effects of maternal control in feeding on daughters’ eating and relative weight are moderate, they are of comparable magnitude with the path coefficient reflecting genetic factors, which directly links the mother’s and daughter’s relative weights. These results indicate that mothers’ child-feeding practices influence daughters’ risk of becoming overweight, and the results show one way that family environmental factors can work synergistically with genetic factors to produce intergenerational similarities in eating and overweight. Heavier mothers have heavier daughters, and these results indicate that these familial resemblances arise from genetic factors and the use of child-feeding practices that foster problems in eating and increase daughters’ relative weight.
The findings of this research support the bidirectionality of influence between parents and children within families; this bidirectional flow of influence is the basis for nonshared environments in families. In the present example, daughters’ weight status influenced mothers’ perceptions of daughters’ risk of overweight, which in turn influenced mothers’ child-feeding practices. The model tested here included only one of many possible nonshared family environmental effects that may influence daughters’ eating and relative weight, namely mothers’ child-feeding practices. Other possible aspects of the nonshared family environment, such as interactions with siblings, the influence of television and other media, and the effects of physical activity patterns, are not included in this model. The results of this research are promising because they show that specifying and measuring even a single, limited aspect of the nonshared family environment can substantially enhance our understanding of the ways in which family environments may foster the development of overweight phenotypes in children.
These findings also provide support for important aspects of Costanzo and Woody’s (10
) obesity proneness model. This model explains how excessive parental control in feeding can result when 1
) parents are particularly invested in their children’s eating; 2
) children are perceived as being at risk of developing eating problems, weight problems, or both; and 3
) parents have trouble controlling their own food intake and assume that their children cannot do so either. Consistent with these points, our results confirmed that a mother’s efforts to control her own weight, as measured by dietary restraint, in combination with her perceptions of her daughter’s risk of overweight, predicted the mother’s use of greater restrictive control in child feeding. These findings are consistent with those of other recent research on parenting practices and children’s development in suggesting that effects flow not only from parent to child, but also from child to parent in that parenting practices are shaped and influenced by the child (8
). In particular, these findings strengthen previous findings indicating that child-feeding practices are influenced by the weight status of the child (11
Costanzo and Woody (10
) contend that excessive control in feeding diminishes children’s capacity for self-regulation. In the current study, this contention was supported by the finding that greater maternal restriction was associated with evidence of difficulties in self-control of food intake by daughters. Daughters’ self-control difficulties were measured by using a composite method that reflected 1
) less evidence of adjustments in food intake in response to changes in the energy density of foods, and 2
) greater intakes of palatable snack foods in the absence of hunger. These findings contribute to a growing body of evidence indicating that use of stringent controls and restrictive child-feeding practices does not produce the intended effect of helping daughters to establish adequate self-control of food intake. Rather, parents’ use of controlling feeding practices may actually promote patterns of intake that are readily influenced by the presence and availability of palatable foods (15
). Additional research is warranted, given that our contemporary environment is characterized by the pervasive availability of large portions of palatable, inexpensive, energy-dense foods (30
The possibility that parents facilitate or promote early dieting and weight concerns among older children and young adolescents was explored in previous research (16
). Daughters who diet by adolescence tend to have mothers who diet, and mothers may encourage daughters to diet and provide coaching on how to do so (17
). The findings of the current study suggest that the intergenerational transfer of eating and weight problems between mothers and daughters may begin during the preschool period, very early in girls’ development. In the present study, mothers with restrained eating styles imposed more control on their daughters’ eating and had daughters who showed evidence of reduced self-control of energy intake. Edmunds and Hill (20
) recently found that 12-y-old children who reported the highest degree of dietary restraint also reported the highest degree of parental control over eating. These findings highlight a need for longitudinal data to examine the role of parental control, especially restriction and monitoring, as a developmental precursor of daughters’ subsequent use of self-imposed dietary restraint for weight control. In particular, more work is needed to evaluate whether control in feeding promotes problematic regulation of eating in young girls that persists into the period when dieting, weight concerns, and restrained eating begin to emerge.
The present study showed that specification and measurement of environmental factors can begin to delineate ways in which nonshared environmental factors operating within families can influence childhood overweight. However, this research involved a variety of limitations, including the fact that the sample consisted exclusively of white, 2-parent families. We chose this sample because the prevalence of dieting and eating problems in this group is particularly high. However, this restricted sample precludes generalization of the findings to other socioeconomic, ethnic, and racial groups. This is especially problematic because the prevalence of overweight is even higher among Hispanic and black children than among non-Hispanic white children (32
). At the same time, the reported prevalences of dieting and weight concerns are lower in racial and ethnic groups other than non-Hispanic whites, which suggests that pathways of influence may differ between racial and ethnic groups. Research on family environmental factors that may promote overweight in these groups is urgently needed. Other limitations relate to our reliance on mothers as the sole source of information about child-feeding practices and daughters’ food intake and perceived risk of overweight. Mothers’ reports of their own dietary restraint and child-feeding practices include bias, but such self-reports are essential in measuring perceptions and attitudes, which play crucial roles in determining parental behavior (33
In conclusion, child-specific aspects of the family environment, including mothers’ perceptions of children’s risk of overweight and mothers’ child-feeding practices, may represent important nonshared environmental influences on daughters’ eating and relative weight. The high prevalence of childhood overweight (32
) and recent evidence linking childhood overweight to increased morbidity and mortality (34
) have led to a consensus that programs to prevent the development of childhood overweight should be of high priority (36
). Given the multifactorial nature of the problem, such prevention efforts will have to include a variety of components that focus on influencing energy intake and expenditure. These results contribute to a growing body of literature (11
) suggesting that preventive interventions for childhood overweight should incorporate anticipatory guidance addressing child-feeding practices and their effects on children’s eating and relative weight.