Ask the Pharmacist

Q) I have heard a number of reports suggesting that vitamin D might be helpful in fighting COVID-19. Is there any truth to this?

A) Vitamin D supplements are one of the most common natural health supplements at local pharmacies and, perhaps, this is true for the rest of Ontario if not all of Canada.

There are numerous studies supporting its benefits in strengthening our bones, increasing muscle strength, helping ward off depression and possibly preventing cancer. Now, some of the world’s foremost experts are wondering if vitamin D also plays a protective role in COVID-19 infections.

To be honest, the data is conflicting as it is for many medical questions but on the whole there may well be some truth to this claim. One scientist stated that vitamin D supplementation is “low hanging fruit”. What this means is that it may well be beneficial for COVID-19 (along with its previously touted benefits for other morbidities) and comes with very little risk.

It is very inexpensive and has a large margin of safety with respect to the very wide range of doses it may be safely taken at. There seemed to be many news reports on vitamin D this week that was based on observational date from a number of countries. These various countries looked back retrospectively at their outbreaks and found an inverse association between vitamin D levels and COVID-19 outcomes.

What this means is that scientists found that, in general, those patients with the lowest levels of vitamin D in their blood streams seemed to be more likely to have a more severe case of COVID-19 as well as higher mortality rates from it. The opposite effect was seen in those infected individuals who had the highest levels of vitamin D. The differences in outcomes were not small either as they easily attained statistical significance as shown by a 15.6% reduction in the risk of a severe infection in patients with normal vitamin D levels compared to those who are deficient in it.

One of the authors, a Dr. Kenny from Trinity College in Dublin, Ireland feels that while she admits the data is far short of conclusive, it is robust enough that she has called upon the Irish government to update their current guidelines. She feels it is a “matter of urgency” that they encourage all adults to take vitamin D supplements during the COVID-19 crisis. This potential effect has a scientific explanation that makes sense as well.

It is well established that vitamin D has an “immune-modulating” effect and can lower inflammation within the body. As such, vitamin D seems to be able to suppress our adaptive immune system which regulates our cytokine levels (these are a large group of proteins that are released by some of the cells in our immune system and act to regulate inflammation and the production of blood cells within the body) thereby, reducing the risk of the so-called “cytokine storm” that seems to immediately precede life threatening respiratory issues with this infection.

The researchers also feel that this recommendation for vitamin D supplementation is a good idea regardless of where you live in the world or how much time you spend outdoors. Vitamin D has long been known as the “sunshine” vitamin because it is produced in your skin in response to sun exposure.

Their support for this recommendation is partially based upon the fact that Northern Italy and Spain had some of the highest COVID-19 mortality rates in the world. Vitamin D deficiency is very high in these countries despite their sunny climates quite possibly due to the fact they do not fortify their foods with vitamin D as we and many more northern European countries do. Countries with much higher blood levels of vitamin D in Europe such as Norway and Finland have fared much better in their mortality rates.

The recommended dose of vitamin D to be taken seems to be a matter of opinion but most feel that the current Health Canada recommendations offer a very wide range (between 400 to 800IU depending upon your age) however most of us would be better served by taking 1000 to 2000 IU’s a day.

Vitamin D costs under $5 for a bottle of 100, can be taken with or without food and have no common drug interactions or medical conditions in which its use is not recommended. Once again, the data is far from crystal clear that vitamin D is actually helpful in COVID-19 but given its safety profile and potential, what have you got to lose?

For more information about this or any other health related questions, contact your pharmacist.