Published on December 21, 2021

Review of nearly two million individuals from 72 combined studies further supports the link between low vitamin D and increased susceptibility to COVID-19 infection, severity and mortality

Key Points

  • Another meta-analysis, which included data from nearly two million participants from 72 combined studies, further supports the connection between low vitamin D and increased risks of COVID-19
  • Vitamin D deficiency/insufficiency was related to a 46% higher risk of developing COVID-19, 90% higher risk of developing severe COVID-19, and 107% higher risk of death due to COVID-19
  • Share this knowledge easily with the new Vitamin D & COVID-19: A Summary of Published Research eBook, available now through the end of the year for free with any kit purchase or donation

A number of studies, such as those included in our new Vitamin D & COVID-19: A Summary of Published Research eBook and on our blog, have provided much evidence showing the significant effect that vitamin D status has on COVID-19 disease progression and outcomes, where higher vitamin D levels can reduce the risk of infection and severity and help prevent death. Findings from yet another meta-analysis, which included data from nearly two million participants from 72 combined studies, further support the connection between vitamin D and the risks of COVID-19. This analysis is reviewed below and will be added to our eBook in the next revision.

Have you taken action on this information yet, for yourself and those around you? Measure your vitamin D level if you haven’t already, and easily share this life-saving information with others. Get your eBook for free with your kit purchase or donation now until the end of 2021!

Another Vitamin D and COVID-19 Meta-Analysis, with Similar Conclusions

A total of 72 studies with data from 1,976,099 individuals was included in the meta-analysis by Dissanayake et al., which was published this month (December, 2021).

The study found that those with vitamin D deficiency/insufficiency had a

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46% higher risk of developing COVID-19 (p<0.0001)

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90% higher risk of developing severe COVID-19 disease (p<0.0001)

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107% higher risk of death due to COVID-19 (p=0.003)

It is important to note that vitamin D deficiency/insufficiency was used to describe vitamin D insufficiency or deficiency of any severity, and was not broken down by specific vitamin D level cut-off points. All findings point to significantly higher risk with lower vitamin D levels. Timing of vitamin D testing in relation to the COVID-19 outcome(s) measured, and the cut-off vitamin D levels used to define deficiency/insufficiency, seemed to have the greatest effect on individual study risk analysis outcomes.

Share this Information and Take Action!

Have you measured your vitamin D level yet? Are those you love aware of this information and of their own vitamin D level?

Share the opportunity to measure vitamin D levels from home as a participant in the vitamin D*action project!  Any kit purchase made now through the end of this year will include the eBook Vitamin D & COVID-19: A Summary of Published Research for free (also free with a donation here).

Thank you for your continued support and in sharing the research on vitamin D!

Vitamin D is an Easily Modifiable Factor to Help Improve Disease Outcomes – Check Your Level Today

Having and maintaining healthy vitamin D levels and other nutrient levels can help improve your health now and for your future. Choose which to measure, such as your vitamin D, omega-3s, and essential minerals including magnesium and zinc, by creating your custom home test kit today. Take steps to improve the status of each of these measurements to benefit your overall health. You can also track your own intakes, symptoms and results to see what works best for YOU.

Enroll and test your levels today, learn what steps to take to improve your status of vitamin D (see below) and other nutrients and blood markers, and take action! By enrolling in the GrassrootsHealth projects, you are not only contributing valuable information to everyone, you are also gaining knowledge about how you could improve your own health through measuring and tracking your nutrient status, and educating yourself on how to improve it.

What Does it Take YOU to Get Your D to 40 ng/ml (100 nmol/L)?

Did you know your health could be greatly affected by making sure you have a vitamin D level of at least 40 ng/ml (100 nmol/L)? Help us help you.

STEP 1 - Do you know what your vitamin D level is? If not, be sure to test today to find out.

STEP 2 – Determine your target level. Are you at your target level? Experts recommend a level of at least 40-60 ng/ml (100-150 nmol/L).

STEP 3 – Need to boost your level? Use the D*calculator to see how much vitamin D it may take to reach your target. Opt for the Loading Dose for a quicker boost.

STEP 4 – Optimize how your body absorbs and utilizes vitamin D with co-nutrients and these simple steps.

STEP 5 – Re-Test! This is an important step to make sure you have reached your target level, and to ensure you are not taking too much! Re-testing after 3-4 months is recommended.

STEP 6 – Adjust, Repeat…

Give your immune system the nutrients it needs to support a healthy you and protect yourself from unnecessary diseases, especially COVID-19.


The first Randomized Controlled Trial on vitamin D and COVID-19 has shown a 96% lower risk of ICU admission for those receiving vitamin D (as 25(OH)D to quickly boost vitamin D blood levels) along with the standard treatment, compared to those receiving standard treatment alone.

These results support many previous observational studies showing a relationship between vitamin D levels and intake and COVID-19 severity.

Review the Latest Nutrient Research for COVID-19

GrassrootsHealth Nutrient Research Institute has launched the new Immune Boost project with the use of our myData-myAnswers nutrient health system that nearly 15,000 people are already using for their health. Specific markers that influence immune health are suggested for testing as part of this project including:

  • Vitamin D
  • Omega-3 Index
  • Essential elements magnesium, selenium, and zinc
  • hsCRP

Our goal is to demonstrate how one can use the Nutrient Research Model established by Dr. Robert Heaney to show the effect of vitamin D serum levels of at least 40 ng/ml (100 nmol/L) on risk reduction for all ethnicities in the population. Status and intake of other nutrients will also be analyzed for any type of relationship to immune status and symptom severity. Join the project today!

Please let us know if you're interested in helping sponsor this project.

CLICK HERE for updates and new information about the project.

Through GrassrootsHealth Nutrient Research Institute, you can also test your essential elements magnesium, copper, zinc and selenium, toxins such as lead, mercury and cadmium, as well as your omega-3 levels, inflammation levels and thyroid stimulating hormone (TSH) level. Find out your levels today! Log on to the test selection page (click the link below) to get your tests and see for yourself if your levels can be improved.

Make sure you track your results before and after, about every 6 months!

Click Here to Access the Test Page

How can I track my nutrient intake and levels over time?

To help you track your supplement use and nutrient levels, GrassrootsHealth has created the Personal Health Nutrient Decision System called

For each specific supplement, you can track what days you take it, how much, and many other details.  This will help you know your true supplemental intake and what patterns of use work for you to reach and maintain optimum nutrient levels. Check it out today!