Vitamin D: Should I be taking a supplement?

Vitamin D plays an important role in many functions of your body.  Getting a healthy, daily dose of vitamin D can be challenging and a common problem for many Canadians. In this video, Dr. Alexandra Papaioannou discusses the sources and health benefits of vitamin D, who should take supplements and how much.


Learn the answers to the following questions:

  • What is vitamin D and why is it important?
  • What are the best food sources for it?
  • Can you get all that you need from food?
  • How would you know if your vitamin D is too low?
  • How effective are vitamin D supplements?
  • What can we do about vitamin D deficiency?

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This work is supported through the McMaster Institute for Research on Aging and funds provided by the Dean and Vice-President, Faculty of Health Sciences at McMaster University.

DISCLAIMER: These summaries are provided for informational purposes only. They are not a substitute for advice from your own health care professional. The summaries may be reproduced for not-for-profit educational purposes only. Any other uses must be approved by the McMaster Optimal Aging Portal (

Many of our Blog Posts were written before the COVID-19 pandemic and thus do not necessarily reflect the latest public health recommendations. While the content of new and old blogs identify activities that support optimal aging, it is important to defer to the most current public health recommendations. Some of the activities suggested within these blogs may need to be modified or avoided altogether to comply with changing public health recommendations. To view the latest updates from the Public Health Agency of Canada, please visit their website.