Background: Disordered eating behaviors are particularly common among adolescent girls. The prevalence of unhealthy weight control behaviors, such as purging, increases from approximately 14 to 24 percent as girls progress from middle to late adolescence. Multiple health issues, including poor diet quality, obesity, depressive symptoms, and the onset of eating disorders, are often associated with disordered eating behaviors.

Retrospective studies of female adolescents and college students have suggested that more frequent family meals may reduce the likelihood of developing disordered eating behaviors and weight-control practices. However, the strength of these findings has been limited by cross-sectional design and potential recollection bias about previous mealtime experiences. Neumark-Sztainer and colleagues designed a five-year longitudinal study to examine the association between the frequency of family meals and disordered eating behaviors in adolescents.

The Study: The authors recruited adolescents who had participated in the Project EAT-I (Eating Among Teens) study five years earlier. Project EAT-I examined eating patterns and frequency of family meals among middle and high school students. For Project EAT-II, participants from the original study were interviewed about their current eating behaviors, including how often their families ate meals together and whether they engaged in disordered eating behaviors. The investigators classified disordered eating behaviors as extreme weight control (e.g., vomiting, diuretics, laxative use); unhealthy weight control (e.g., restricting food intake, smoking cigarettes for appetite control); chronic dieting; or binge eating. Participants were also asked about the perception of their family's connectedness and whether they had parental pressure to diet. Trained research assistants measured participants' body mass index (BMI) when possible. Self-reported height and weight were substituted in most cases when a BMI was not obtainable.

Results: A total of 2,516 adolescents (1,386 girls and 1,130 boys) participated in the initial and follow-up studies. One third of participants had been in middle school during the initial study (mean age 12.8 years) and two thirds had been in high school (mean age 15.8 years). The study population was 48.5 percent white, 19.2 percent Asian, and 19 percent African American, with other ethnic backgrounds comprising the remainder of the group.

All categories of disordered eating behaviors were significantly more common among girls who previously had fewer than five family meals per week compared with those who had more frequent family meals (i.e., 26 versus 17 percent for extreme behaviors, 64 versus 57 percent for unhealthy behaviors, 13 versus 9 percent for binge eating, and 18 versus 14 percent for chronic dieting). After adjusting for BMI, sociodemographic characteristics, parental pressure to diet, and family connectedness, girls were still less likely to use extreme weight control behaviors if they had participated in at least five family meals per week (odds ratio, 0.71). Although other disordered eating behaviors were not significantly reduced after multivariable analysis, a modest protective effect of frequent family meals occurred in all areas. In contrast, no protective effect of frequent family meals occurred with boys, and certain unhealthy weight control behaviors (e.g., skipping meals, eating very little food) were somewhat more common at the follow-up evaluation.

Conclusion: This longitudinal study, the first of its kind, showed that participating in regular family meals helped protect girls from extreme weight control behaviors five years later. These results add to the growing body of evidence that family meals may contribute to the health and well-being of girls. Frequent family meals showed no protective effect in boys. The authors speculated that this might be because adolescent boys and girls experience family meals differently. Adolescent girls may be more likely to be influenced by interpersonal and familial relationships than adolescent boys. The data suggest it is important for health care professionals to emphasize the possible benefits of family meals for adolescent girls.