Dietary Supplement Use Among Participants of a Databank and Biorepository at a Comprehensive Cancer Centre

Objective: We assessed the prevalence, patterns and predictors of dietary supplement use among participants of the databank and biorepository (DBBR) at a comprehensive cancer centre in western New York.

Design: Archived epidemiological questionnaire data were obtained from the DBBR at Roswell Park Cancer Institute. Descriptive statistics and logistic regression explored the prevalence, patterns and predictors of lifetime use of four common supplements (multivitamins, vitamin C, vitamin E and calcium) and use of multivitamins, sixteen single vitamins/minerals and eighteen herbal/specialty supplements within the previous 10 years.

Setting: Western New York, USA.

Subjects: DBBR participants (n 8096) enrolled between December 2003 and July 2012 were included in these analyses: 66.9 % (n 5418) with cancer, 65.6 % (n 5309) women, mean age for patients v. cancer-free controls 59.9 (SD 12.6) years and 50.7 (SD 15.4) years, respectively.

Results: Overall, 54.4 % of DBBR participants reported lifetime use of one or more supplements and 63.1 % reported use of one or more supplements within the previous 10 years (excluding multivitamins). Multivitamin use was high in this sample (lifetime: 64.1 %; 10 years: 71.3 %; current: 51.8 %). Supplementation was higher among cancer-free controls than cancer patients. Vitamin C, calcium and fish oil were the most common single vitamin, mineral and specialty product, respectively.

Conclusions: A consistently high and increasing proportion of dietary supplement use over time remains clear. Supplementation is prevalent among cancer patients and may even be higher than predicted in cancer-free individuals. Further studies should assess the safety and efficacy of specific supplements in reducing disease risk.