Associations among Dietary Supplement Use and Dietary and Activity Behaviors by Sex and Race/Ethnicity in a Representative Multiethnic Sample of 11th-Grade Students in Texas

Background and objective The purpose of this study was to examine associations among dietary supplement use and dietary/activity patterns in a representative sample of adolescents by sex and race/ethnicity, a research area where extant data is limited. Design/participants Cross-sectional, multistage, probability-based sample of 11th graders in Texas during 2004-2005 (n=6,422; 48.8% white/other, 37% Hispanic, and 14.2% African American; 50.6% boys; mean age 16.7 years). Setting Classrooms. Main variables assessed Dietary supplement use, dietary/activity patterns, and anthropometrics. Statistical analyses performed Multiple logistic regression models (odds ratios [ORs] and 95% confidence intervals [CIs]). Results Dietary supplement users reported healthy dietary and physical activity behaviors overall, yet sex- and race/ethnicity-specific differences were seen in associations among specific diet/activity behaviors and supplement use. In whites/others and Hispanics, but not African Americans, supplement use was associated with higher diet quality scores (OR 2.93, 95% CI 1.74 to 4.95 for whites/others; OR 3.93, 95% CI 2.26 to 6.83 for Hispanics), and regular consumption of breakfast (OR 2.27, 95% CI 1.40 to 3.66 for whites/others; OR 1.96, 95% CI 1.11 to 3.46 for Hispanics) and low-fat foods (OR 3.02, 95% CI 1.53 to 5.98 for whites/others; OR 3.59, 95% CI 1.11 to 11.6 for Hispanics). Supplement use was not associated with body mass index or with sedentary behaviors overall, but was associated with less television viewing only in whites/others (OR 0.53, 95% CI 0.33 to 0.84). For physical activity, boys and whites/others showed positive associations between supplement use and all indicators examined, but girls, Hispanics and African Americans showed mixed patterns of associations. Supplement use was associated with higher weight preference only in boys (OR 2.47, 95% CI 1.24 to 4.90), and vegetarian diets only in girls (OR 2.96, 95% CI 1.35 to 6.47). Conclusions Dietary and activity patterns associated with dietary supplement use may vary by sex- and racial/ethnic subpopulation, especially amongst African American youth. These findings together with further research on psychosocial and attitudinal characteristics associated with adolescent supplement use can enhance the development of targeted and tailored health communications about supplement use in adolescent subpopulations. J Am Diet Assoc. 2011;111:385-393.