Vitamin and Mineral Supplement Use among US Medical Students: A Longitudinal Study
Abstract
Objective
To provide data on medical students’ multivitamin and calcium supplement use during medical school.
Design
Medical students were anonymously surveyed at three time points: freshman orientation, orientation to wards, and during senior year.
Subjects
Medical students (n=2,316) at 16 US medical schools (response rate=80.3%).
Outcome Measures
Prevalence and correlates of multivitamin and calcium supplement use throughout medical school.
Statistical Analyses
χ2 tests with associated P values, and logistic regression with associated odds ratios and confidence intervals.
Results
Half of medical students surveyed used multivitamins, and 19% used calcium supplements, at least once per week as freshmen. Consumption of calcium, but not multivitamin, supplements increased during subsequent years (P=0.0001) and both supplements were more commonly used by women (P<0.0003). Of 970 students tracked across all three time points, 14% of women, compared with only 2% of men (P<0.0001), took calcium at all three time points. Using multivariate models, we found that medical students were more likely to use multivitamins if they exercised regularly, had children, were underweight, or were women who were not heavy users of alcohol (P<0.0001 to P<0.05). Similarly, students who were women, underweight, exercised regularly, or had a personal or family history of osteoporosis were more likely to consume supplemental calcium (P<0.0001 to P=0.04).
Conclusions
Medical students of all types used supplements at moderate rates, and women used supplements more commonly and consistently than did men. Medical students, especially nonunderweight and nonexercising students, may be particularly important targets for messages regarding appropriate and adequate vitamin/mineral use.
Address correspondence to Erica Frank, MD, MPH, Department of Health Care and Epidemiology, University of British Columbia, 5804 Fairview Ave, Vancouver, BC, Canada V6T 1Z3.