Differences in body composition, physical activity, and dietary intake by birthplace in youth of Mexican origin

One of the goals of Healthy People 2010 is to reduce health disparities among different racial and ethnic segments of the U.S. population. The purposes of the study were threefold: (a) to determine the extent to which acculturation was associated with practical estimates of body composition; (b) to determine whether the proxy variables of acculturation were associated with potential behavioral mediators of body composition such as physical activity and selected dietary intakes; and, (c) to determine whether the interrelationships among the proxy target variables of acculturation, the outcome variables of body composition, and the potential mediator variables of physical activity and diet would differ by the potential mediator variables of sex and family history of overweight in youth of Mexican origin aged 12-19 years. Eighty-four participants recruited from seven places in Salt Lake City and the surrounding area in Utah completed all the data collection including demographic survey, body mass index (BMI), waist circumference (WC), three skinfold sites, physical activity, and diet measures. Sixty-four percent of the participants were U.S.-born and 36% were Mexico-born. Independent t-test analysis revealed that there were no birthplace-related differences between the two groups regarding body composition and selected dietary intakes except for daily physical activity, showing that Mexico-born youth took more steps on weekend days than that their U.S-born counterparts (p = 0.019). Gender difference was found to be significant; male youth took more average daily steps than female youth (p = 0.022). Approximately 5% of the participants met the recommended physical activity amounts. As opposed to our hypothesis, mean intake for fruit servings was higher in U.S.-born than in Mexico-born youth (p = 0.038). None of the individual dietary intake was correlated with body composition, physical activity, and a proxy variable for acculturation after adjusting for total caloric intake. However, the present study lacked sufficient power to detect the hypothesized associations among the outcome variables. More research is clearly needed to address this growing understanding of the causal pathways using birthplace as a predictor in youth of Mexican origin who may be particularly at high risk of becoming obese adults.