Published on December 9, 2020

Vitamin D supplementation to achieve a serum level of 50 ng/ml improved conversion of SARS-CoV-2 positive to negative 3-fold by week 3

Vitamin D plays many important roles within the immune system, such as influencing the expression of genes involved in the immune response, regulating inflammation, and activating certain immune cells and molecules. The research demonstrating a link between vitamin D deficiency and COVID-19 severity is now quite strong. In fact, based on this evidence over 100 doctors and scientists are calling for widespread vitamin D use to reduce the risk and severity of COVID-19.

The paper reviewed below is yet another in a lengthy list that emphasizes the importance of vitamin D supplementation and attaining a target serum level of 40-60 ng/ml (100-150 nmol/L) in the fight against the global COVID-19 pandemic.

Supplementing with Vitamin D to Reach a Target Level of 50 ng/ml (125 nmol/L)

A study by Rastogi et al. randomized 40 patients who were hospitalized with a SARS-CoV-2 positive test and who were vitamin D deficient (with levels below 20 ng/ml or 50 nmol/L) into a study to determine if short-term, high-dose vitamin D supplementation with a target vitamin D level of 50 ng/ml (125 nmol/L) had an effect on SARS-CoV-2 test status. One group (n=16) received 60,000 IU of vitamin D per day for 7 days, while the other group (n=24) received a placebo. Vitamin D levels were tested again after 7 days; for those in the vitamin D group whose level was still below 50 ng/ml, daily vitamin D supplementation continued. All patients received the standard care for SARS-CoV-2 infection. Re-testing for SARS-CoV-2 was done on day 5, 7, 10, 14, 18 and 21. The primary outcome measured was the proportion of participants in each group who tested negative for SARS-CoV-2 before week 3.

A Big Difference Seen with Vitamin D!

Vitamin D levels at the beginning of the study were very low for both groups: 8.6 ng/ml (21.5 nmol/L) for the vitamin D group and 9.5 ng/ml (23.7 nmol/L) for the placebo group. Among the 16 participants receiving vitamin D, 10 reached a vitamin D level of at least 50 ng/ml after 7 days of supplementing, with another two reaching 50 ng/ml by day 14.

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By the end of 3 weeks, as illustrated in the chart above, ten of the 16 participants (63%) in the vitamin D group became SARS-CoV-2 negative, compared to only five of the 24 participants (21%) in the control group (p=0.018). Three times more participants in the vitamin D group converted from SARS-CoV-2 positive to negative after 3 weeks compared to those who did not receive any vitamin D. This strongly indicates that supplementing with vitamin D to reach a serum level of at least 50 ng/ml (125 nmol/L) among asymptomatic and mildly symptomatic SARS-CoV-2 positive individuals provides a much greater chance of testing negative compared to those who are vitamin D deficient.

Also important to note was the safety profile of vitamin D, with no indication of toxicity in the vitamin D group.

The Conclusion

As the authors state,

“oral vitamin D supplementation to augment 25(OH)D above 50 ng/ml helped to achieve SARS-CoV-2 RNA negativity in greater proportion of asymptomatic vitamin D deficient individuals with SARS-CoV-2 infection… supplementation may help in reducing transmission rates of the highly contagious SARS-CoV-2 infection.”

In other words, test now to find out your vitamin D level, and take the necessary steps to achieve your target level. You can use the vitamin D*calculator to determine what dose of vitamin D may be right for you, including a bolus dose option to raise levels more quickly.

Summary: Vitamin D & COVID-19

It’s TIME to start saving lives! If you can help PREVENT the majority of the death, it’s time! What’s it costing you/us not to take action NOW?

There is much published research that supports a clear link between vitamin D and COVID-19 showing that higher vitamin D levels are related to:

a decreased risk of testing positive for COVID-19

better clinical outcomes among patients with COVID-19

less severe COVID-19 disease

decreased risk of death due to COVID-19

Everyone needs vitamin D! Here’s how to tell how much you might need, and who may need more – people who are overweight or who have darker skin are among those at increased risk of deficiency.

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Be sure to educate yourself on the benefits and importance of vitamin D for immune health, and take steps to ensure you and your loved ones are getting enough.

You can review all of the COVID-19 and immune health information we have shared on this page.

Ensure Vitamin D Levels of 40-60 ng/ml (100-150 nmol/L) for You, Your Children, Loved Ones

Correcting a vitamin D deficiency at any age and any time of life decrease potential disease severity and improve outcomes! Test your vitamin D level today, learn what steps to take to improve your level, and take action to achieve and maintain a vitamin D level of 40-60 ng/ml (100-150 nmol/L).

Using the GrassrootsHealth Custom Kit Builder, you can create a test kit that measures your status of vitamin D and other important nutrients (such as omega-3s, zinc and magnesium), as well as your CRP level to measure inflammation. Click here to build and order your test kit today – measure your status and take the steps necessary to improve them if needed; make an impact on your health today and for your future! When you know what your levels are, you can determine next steps to take and how much supplementation may be needed if you are not at your target levels.

Enroll now with the Full Immune Boost Panel (which includes tests for vitamin D, Omega-3 Index, magnesium, zinc, selenium, copper, and hsCRP), and get 10% off when you use coupon code BoostTen at checkout.

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!