The link between Vitamin-D And COVID-19

Mike Collette • September 23, 2020

The link between Vitamin-D and COVID-19

By: Sam Russo (Prototype Nutrition Dietician)

The link between vitamin d and covid-19 prototype

Think back to mid-March, when Massachusetts was overwhelmed with Coronavirus cases and we had more questions than answers. Over these past six months, we have learned so much about this disease that literally did not exist even a year ago. The more we learn, the better equipped we are to live in this new normal, so this blog post is created with the intention of providing you with just a bit more information about the virus.

 

Now, I am not a doctor and I certainly cannot give you medical advice. That would be illegal. However, as a Registered Dietitian, I have a responsibility to stay up-to-date with the most recent nutrition research. One of the hottest topics in the nutrition world is whether or not there is a link between vitamin D and COVID-19. Do individuals that have been hospitalized with COVID-19 have lower levels of vitamin D? Does a vitamin D supplement lessen the risk of being infected? Is there even a correlation at all and, if so, does one cause the other? These are the questions that researchers have been trying to answer, and here is a brief analysis of some of the findings.

 

Vitamin D is a fat-soluble vitamin that primarily comes from sunlight. It is also naturally found in fish oil and mushrooms, so it can be obtained through food sources as well. Deficiencies in this vitamin often manifest in rickets (à la tiny Tim from the Christmas Carol) and changes in mood (such as with Seasonal Affective Disorder). There has also been a proven link between vitamin D and respiratory health. According to studies that date back to the early 2000s, increased levels of vitamin D can lessen symptoms of patients with tuberculosis, cystic fibrosis, COPD, asthma, and the seasonal flu. 1 As a result, US Registered Dietitians often recommend that these patients supplement their diet with liquid vitamin D 3 .

 

Now that research has shown that COVID-19 is a respiratory illness, the hypothesis is that vitamin D can also lessen symptoms for this virus. While some studies show that there is no evidence to support the hypothesis, others show a potential correlation. 2 Other studies show that vitamin D supplementation may have its benefits for people in the hospital, but an undetermined effect on people who have yet to be hospitalized. 3 Regardless of the outcomes of the study, nearly all the readings I have done suggest that there is a potential inverse correlation between vitamin D levels and COVID-19. 4, 5, 6 Simply put, that means that, as a whole, people who test positive for Coronavirus tend to have lower levels of vitamin D.

 

So what does that mean for you? Well, having adequate levels of vitamin D certainly does not make you immune to contracting Coronavirus. It means that there is a potential that having adequate levels of vitamin D could make you less susceptible or lessen the severity of symptoms. “Could” being the operative word here. More research is still needed to make any confident conclusions about the efficacy of vitamin D supplementation on preventing or lessening the severity of COVID-19.

 

My recommendation – definitely supplement with vitamin D! Supplement daily with 400-600 IU liquid vitamin D3 , which can be ordered online or found at most natural health stores. If these preliminary studies are wrong and there ends up being no relation between the two, there is no harm in supplementing with appropriate amounts of vitamin D. If the hypothesis is correct, then you’ll have that covered too. As the weather gets colder and you are inside more, you may want to increase daily intake to 1,000 IU for a week or two, especially if you are already deficient.

 

So stay safe everyone! If you’re interested in reading the scientific papers I referenced in this post, here are my sources. I highly encourage you all to keep researching, just remember – google scholar is your best friend when it comes to finding reliable and accurate information. Emphasis on “scholar”!

 

 

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