Published on December 15, 2021

PLUS, the Vitamin D & COVID-19: A Summary of Published Research eBook is now available in its first version!

Key Points

  • There is 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
  • Vitamin D plays roles within the immune response that are especially influential in fighting a SARS-CoV-2 (COVID-19) infection
  • Share this knowledge easily with the new Vitamin D & COVID-19: A Summary of Published Research eBook, available now for purchase


How Vitamin D Works to Fight COVID-19

A number of studies, such as those included in our new eBook, 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. How does vitamin D work within the body to have such a protective effect?

The following diagram by Ghelani et al. is an excellent illustration of how the presence or absence of vitamin D could determine the overall effect a SARS-CoV-2 infection has within the lungs and on disease progression. As shown in blue, vitamin D sufficiency can help protect the lungs from acute injury due to infection from SARS-CoV-2, while vitamin D deficiency contributes to a defective immune response and increased disease severity and death, as illustrated in orange.

Click to Enlarge & Print

Vitamin D plays roles within the immune response that are especially influential in fighting a SARS-CoV-2 (COVID-19) infection

Infection begins when the SARS-CoV-2 virus enters the cells of the lung by binding the angiotensin-converting enzyme 2 (ACE-2) receptor, de-activating it and resulting in inflammation. This interrupts what is called the renin-angiotensin system (RAAS), a pathway responsible for regulating blood volume, fluid and electrolyte balance, and systemic vascular resistance.

When vitamin D is available in sufficient amounts, it is able to fulfill its roles to

  • regulate the renin-angiotensin system (RAAS)
  • increase ACE-2 expression, which leads to anti-inflammatory actions that help protect the lungs, keep inflammation levels down, and reduce the risk of cytokine storm
  • prevent the toxic accumulation of the pro-inflammatory molecule angiotensin-II (ANG II) and angiotensin-converting enzyme (ACE)
  • increase immune cells with antioxidant properties, anti-inflammatory actions, and anti-microbial peptides through its actions within the immune system

With additional research showing that

  • vitamin D receptors are found in high concentrations in various immune cells that are vital to a successful immune response, especially dendritic cells, macrophages, T and B lymphocytes
  • the enzyme that converts 25(OH)D3 into 1,25(OH)2D3 is present in high levels in macrophages and the epithelia of the respiratory system specifically
  • and, vitamin D has been found to disrupt the function of 19 out of 27 (70%) SARS-CoV-2 proteins

It’s no wonder that “…low levels of vitamin D can result in dysfunction of crucial antimicrobial effects, potentially contributing to poor prognosis.”

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!