Psychosocial Correlates of Dietary Supplement Use: Results from the National Survey of Midlife Development in the United States.

Drawing on data gathered in the National Survey of Midlife Development in the United States, this study examined internal and external locus of control, self-esteem, neuroticism, perceived health status, uniqueness, and somatic amplification as correlates of dietary supplement use. With sex, race, and age measures also included in the study, bivariate analyses showed greater supplement use among women and older respondents as well as those scoring higher on internal locus of control, self-esteem, perceived health status, and somatic amplification. Regression analyses identified sex and internal locus of control as the strongest predictors. Interactions between age and external locus of control also emerged.