Mark McAllister, MD

Dong JY, Iso H, Kitamura A, Tamakoshi A. Multivitamin Use and Risk of Stroke Mortality: The Japan Collaborative Cohort Study. Stroke. 2015

Many patients seeking to improve their overall health and reduce risk of disease turn to the vitamin store. A plethora of products are available and represent a multibillion dollar industry. Previous investigations are divided in whether vitamins reduce the risk of cardiovascular disease, cancer, or other diseases—including the possibility that vitamin supplementation may actually increase risks. The effects of multivitamins on stroke outcomes are not clear.

The Japan Collaborative Cohort study involves collection of many types of data regarding lifestyle habits and health outcomes. Over 72,000 patients were included in this analysis, looking at the risk of death due to stroke by their self-reported multivitamin use. In the adjusted analysis there was a trend towards lower stroke-related mortality in the multivitamin users, but this did not reach statistical significance. In a subgroup analysis there was a significant reduction in stroke mortality in multivitamin users eating fruits and vegetables fewer than three times a day. This effect was not seen in individuals eating fruits and vegetables three or more times a day.

Should we advise patients to add multivitamins to their daily regimen to reduce their risk of stroke? I think it’s difficult to arrive at that conclusion from this observational study. What is likely best is that we continue to advocate for overall healthy patterns of behavior, including a varied diet rich in fruits and vegetables. Reliance on an easy fix in pill form is unlikely to substitute for lifelong healthy habits.