BACKGROUND: This study compared moderate-to-vigorous physical activity (MVPA) and sedentary behavior in U.S.-born and foreign-born adolescents and young adults, and differences in behavior change from adolescence to young adulthood by nativity. METHODS: Data on 2039 U.S.-born and 225 foreign-born participants from Project EAT-III (Eating and Activity in Teens and Young Adults) were used to examine MVPA, television/ DVD/video viewing, and computer use. Participants completed surveys at baseline in Minneapolis/St. Paul, MN secondary school classrooms in 1998-1999 (14.9 +/- 1.6 y) and follow-up measures online or by mail in 2008-2009 (25.3 +/- 1.6 y). RESULTS: At both time points, foreign-born participants reported significantly lower levels of MVPA than their U.S.-born counterparts (P < .05). Foreign-born females at baseline and follow-up and foreign-born males at follow-up reported less television/DVD/video viewing compared with U.S.-born participants (P < .01). All participants experienced a significant decline in MVPA from baseline to follow-up (P < .001). Between-group analyses revealed a significantly greater decline in television/DVDs/video viewing for the foreign-born males compared with U.S.-born males from baseline to follow-up (mean change: foreign-born: -4.8 +/- 1.32 hrs/wk, U.S.-born: -0.6 +/- 0.6 hrs/wk; P < .01). CONCLUSIONS: Differences in activity patterns between foreign-born and U.S.-born youth into young adulthood may contribute to disparities in chronic disease risk. Nativity, along with the social, environmental, and cultural context, should be considered when designing programs to promote MVPA and prevent obesity.

This study used balance theory to illuminate the relations of eating-related attitudinal consistency between self and friends to psychological well-being and eating behaviors. It was hypothesized that attitudinal inconsistency, relative to consistency, would predict lower well-being and poorer eating habits. A population-based sample of 2287 young adults participating in Project EAT-III (Eating Among Teens and Young Adults) completed measures of psychological well-being, eating behaviors, and eating-related attitudes from the standpoint of self and friends. Of participants who cared about healthy eating, those who perceived that their friends did not care about healthy eating had lower well-being and less-healthy eating behaviors (fewer fruits and vegetables and more sugary beverages per day) than those who perceived that their friends cared about healthy eating. Conversely, among participants who did not care about healthy eating, those who perceived that their friends cared about healthy eating had lower well-being and less-healthy eating behaviors (more snacks per day) than those who perceived that their friends did not care about healthy eating. In accord with balance theory, young adults who perceived inconsistent eating attitudes between themselves and their friends had lower psychological well-being and generally less-healthy eating behaviors than people who perceived consistent eating attitudes.