Vitamin D Levels and Covid-19
In the early days of Covid 19 lockdowns, many patients were asking us about vitamin D and Covid infections. While vitamin D has been shown many times over to be an important contributor to immune response, especially pertaining to respiratory infections, it was too early to say definitively what role vitamin D levels played in regards to covid-19.
Now that we are over a year into "flattening the curve" (irony intended), there has been a good amount of information that has emerged looking at vitamin D levels and Covid.
In this week's article, I will take a brief look at one such study.
A study published in the February 2021 edition of the "Journal of Medical Virology" looked at serum Vitamin D levels and it's relationship with outcomes of Covid infections. The study was a systematic meta analysis that went through and examined the results of six other studies and compiled all the pertinent results. The studies combined had a sample size of 311 patients who had been diagnosed with Covid and looked specifically at their serum vitamin D levels and their prognosis.
Of the 376 patients in the sample, the mean serum D level was 21.9 nmol/L. The 150 patients who had a significantly worse prognosis were found to have much lower serum vitamin D levels compared to the 161 patients with a better prognosis who had significantly higher serum vitamin D levels.
I chose this one study to write about as opposed to many others because I believe this study is representative of the relevant vitamin D and Covid studies that have been getting published. In a nutshell, vitamin D supplementation has not been found to be an effective prevention of Covid or a treatment of Covid, HOWEVER, most studies looking at the topic have found that folks with higher vitamin D levels (through supplementation and sun exposure) have fared far better if they become infected with Covid.
To summarize, we have always advocated for vitamin D-3 supplementation in the winter and moderate amounts of sun exposure in the spring and summer months to elevate levels of vitamin D. Vitamin D has long been shown to play an important role in immune function and the studies looking at a relationship between D and Covid have been promising so far.
Munshi R, Hussein MH, Toraih EA, Elshazli RM, Jardak C, Sultana N, Youssef MR, Omar M, Attia AS, Fawzy MS, Killackey M, Kandil E, Duchesne J. Vitamin D insufficiency as a potential culprit in critical COVID-19 patients. J Med Virol. 2021 Feb;93(2):733-740. doi: 10.1002/jmv.26360. Epub 2020 Oct 10. PMID: 32716073.