Evidence for the safety and effectiveness of dietary supplements is mixed. The extent to which older people use dietary supplements concomitantly with conventional medications is often under-appreciated by physicians. We conducted a literature review on clinical considerations associated with dietary supplement use, focusing on benefits and harms, motivations for use and contribution to polypharmacy among older people. Vitamin D ≥ 800 IU has demonstrated benefits in fracture prevention. Vitamins A, E, and β-carotene have been associated with an increase in total mortality in several meta-analyses. A range of non-vitamin dietary supplements have been studied in randomized controlled trials but their efficacy remains largely unclear. Supplement use has been associated with a range of adverse events and drug interactions yet physicians rarely initiate discussions about their use with older patients. Older people may take dietary supplements to exercise control over their health. Given the contribution of supplements to polypharmacy, supplements may be targeted for "deprescribing" if the risk of harm is judged to outweigh benefits. This is best done as part of a comprehensive, patient-centered approach. A respectful and non-judgmental discussion may result in a shared decision to reduce polypharmacy through cessation of dietary supplements. KEY MESSAGES Herbal medications and other dietary supplements are highly prevalent among older people. Physicians are often unaware that their patients use herbal medications and other dietary supplements concomitantly with conventional medications. Herbal medications and other dietary supplements contribute to high rates of polypharmacy, particularly among older people with multimorbidity. Herbal medications and other dietary supplements can interact with conventional medications and be associated with a range of adverse events. Physicians need to be patient-centered and non-judgmental when initiating discussions about herbal medications and other dietary supplements. This is important to maintain and develop patient empowerment and self-management skills.
Keywords: Adverse events; aged; dietary supplements; herbal medications; polypharmacy; shared decision making.