of overweight was studied in 8,186 girls and 7,155 boys, 9 to 14 years of age, who were participating in a national growth and development study . Among children who were mostly or exclusively breast-fed during the first 6 months of life, compared to children who were mostly or exclusively formula-fed, the odds ratio for being overweight was 0.78. This held true when controlling for maternal BMI and other variables reflecting SES and lifestyle activities. It should be noted that not all studies replicated this significant association , and that one study found the association to be true in non-Hispanic white families but not African American families .
The mechanisms for the apparent protective effect of breast-feeding on overweight development were unknown, although recent data implicate parental feeding patterns as a possible factor. Specifically, mothers who breast-fed their infants were less restrictive in their feeding practices (as measured by self-report questionnaire) than mothers who bottle-fed their infants . As discussed in the next section, restriction of child eating may impede a child’s ability to self-regulate food intake and instead teach a child to eat in response to external cues . Whether or not this is the actual mechanism needs to be clarified in future research.
An extensive literature has examined which parental feeding practices, if any, are associated with increased child food intake during meals and increased weight status . Investigators have measured feeding practices by parent-report questionnaires, direct observation, or analysis of videotapes, with the most common assessment tool being the parent-report Child Feeding Questionnaire . A recent review of this literature concluded that, across the range of parental feeding domains that have been studied, only restriction of child eating was consistently associated with increased child total energy intake and weight status . Parents who restrict their children’s access to foods tend to have heavier children. No other feeding domains were associated with childhood obesity, including use of food to calm infants and children, feeding on schedule, pushing child to eat more, and provision of structure during feeding, or using food as a reward [45, 46].
Several mechanisms by which parental restriction may promote increased child energy intake and body weight have been proposed. First, restrictive feeding practices may impede on a child’s ability to adhere to internal hunger and satiety cues (i.e., impaired self-regulation) and thereby teach children to eat in response to external cues (e.g., portion size, time of day). Among preschool children, the ability to self-regulate food and energy intake across meals was poorer among children whose parents reported elevated efforts to control child eating . Second, restricting children’s