STORY AT-A-GLANCE
GrassrootsHealth recently conducted a review of an observational study involving 212 patients who had COVID-19, identifying a correlation between vitamin D levels and disease severity. Those with the mildest disease had the highest vitamin D levels, and vice versa
A second study found those with a vitamin D level between 20 ng/mL and 30 ng/mL had a sevenfold higher risk of death than those with a level above 30 ng/mL. Having a level below 20 ng/mL was associated with a 12 times higher risk of death, compared to having a level above 30 ng/mL
The color of your skin has correlations to your vitamin D level, and we’re also seeing racial disparities in COVID-19. In Detroit, Michigan, where blacks account for 14% of the population, they account for 40% of COVID-19 deaths
It’s important for people with darker skin to realize that the more melanin you have, the more sun exposure you require to make sufficient amounts of vitamin D, and many may need to take a supplement
According to the research done by GrassrootsHealth’s panel of 48 vitamin D researchers, 40 ng/mL is the lower edge of optimal, with 60 ng/mL to 80 ng/mL being ideal for health and disease prevention
In this interview, I interview three vitamin D experts about the importance of vitamin D for improving your immune function and resistance to viral infections of all kinds, including COVID-19.
Bruce Hollis, Ph.D., with the Medical University of South Carolina, has researched vitamin D since the late 1970s. His research associate at the Medical University of South Carolina is Dr. Carol Wagner, who is a neonatologist and has been researching vitamin D since 2000.
Carole Baggerly is the director and founder of GrassrootsHealth Nutrient Research Institute, a nonprofit public health research organization dedicated to moving public health messages regarding vitamin D from research into practice. Baggerly received our Game Changer Award in 2018. She started her work in vitamin D after treatment for breast cancer in 2005.
Vitamin D Levels Correlate With Disease Severity
GrassrootsHealth recently conducted a review of an observational study involving 212 patients in Southeast Asia who had COVID-19, identifying a correlation between vitamin D levels and disease severity. Those with the mildest disease had the highest vitamin D levels, and vice versa.
Of the 212 people, 49 had mild disease; 59 had ordinary disease; 56 were severe and 48 were critical. In the initial study group of 212 patients (see Table 1 below), 55 had normal vitamin D levels, which was defined as greater than 30 ng/ml; 80 had insufficient levels of 21 to 29 ng/ml and 77 had deficient levels of less than 20 ng/ml.
Now, it’s worth noting that the “optimal” vitamin D level in that study was set at 30 nanograms per milliliter (30 ng/mL), which may actually be suboptimal. According to the research done by GrassrootsHealth, 40 ng/mL is the lower edge of optimal, with 60 ng/mL to 80 ng/mL being ideal for health and disease prevention. Despite that, the benefit of having a vitamin D level above 30 ng/mL was clear.
Vitamin D Levels Correlate With Mortality Risk
A second study looked at the data from 780 hospital patients in Indonesia. The same vitamin D level cutoffs were used in this study: below 20 ng/mL; between 20 ng/mL and 30 ng/mL; and above 30 ng/mL.
After adjusting for confounding factors, those with a vitamin D level between 20 ng/mL and 30 ng/mL had a sevenfold higher risk of death than those with a level above 30 ng/mL. Having a level below 20 ng/mL was associated with a 12 times higher risk of death. As noted by Hollis, “That's really strong data.”
It’s Your Vitamin D Blood Level That Matters, Not the Dose
Now, many vitamin D studies conclude that vitamin D supplementation has little or no effect on any given health problem or condition. But there’s a very simple reason for this: Virtually every one of these studies use the same dosage or dosages for everyone, and do not measure participants’ blood levels.
This is a crucial mistake, as it’s really the blood level that needs to get over a particular threshold, and the dosage required to get there can vary widely. Another problem is the fact that most studies use far too low a dosage. If the dosage is too low, you cannot get your blood level into the protective range, and thus it will appear as though vitamin D is useless.
A third factor that can influence the outcome of vitamin D studies is the interaction between vitamin D and other nutrients. Competing deficiencies can affect a particular sub cohort or population, thereby obfuscating results.
A fourth factor is how you define deficiency — using a “word” versus a serum level. For the GrassrootsHealth Scientists’ Panel of 48 researchers, the consensus is that minimum serum level should be 40 ng/ml (100 nmol/L). Wagner explains:
Hollis adds:
Laws Need Updating
Unfortunately, with labeling laws the way they are, it’s very difficult to get this point across. As noted by Baggerly:
Skin Color Impacts Your Vitamin D Deficiency Risk
The color of your skin has correlations to your vitamin D level, and we’re also seeing racial disparities in COVID-19. As noted by Hollis, in Detroit, Michigan, where African-Americans account for 14% of the population, they accounted for 40% of COVID-19 deaths.
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Vitamin D deficiency likely plays a role in this racial disparity, although nutrition, obesity and diabetes rates also contribute to immune dysfunction. It’s important for people with darker skin to realize that the more melanin you have, the more sun exposure you require to make sufficient amounts of vitamin D.
According to Hollis, it’s physiologically impossible for a dark-skinned individual in the United States, unless they're in Southern Florida or Hawaii, to get optimal vitamin D from typical sun exposure.
Daily Supplementation May Strengthen Lung Tissue
If for whatever reason you cannot get regular sun exposure, then vitamin D supplementation is advisable. Ideally, you’ll want to take it daily, opposed to taking a large bolus dose once a week or once a month. As noted by Hollis, studies have consistently shown only daily supplementation were effective.
Baggerly adds:
Vitamin D3’s ability to strengthen the endothelial structure of the lungs may be one way in which vitamin D helps protect against COVID-19. “COVID-19 attacks the lungs … and vitamin D in this model showed to stabilize that,” Hollis says.
Vitamin D Strengthens and Regulates Immune Function
Vitamin D also has a clear effect on your innate immune system, which is your first line of defense against bacteria and viruses, as well as your adaptive immune system, which involves your T regulatory helper and suppressor cells, and natural killer cells.
All of these need to be in balance, Wagner explains. If an imbalance occurs, you can end up with a cytokine storm. According to Wagner, vitamin D is very effective for regulating and balancing adaptive immunity. One example demonstrating the elegance of this system is pregnancy. Wagner explains:
Research has also demonstrated that pregnant women with optimal vitamin D levels significantly reduce their child’s risk of developing Type 1 diabetes, which is an autoimmune disorder. As noted by Baggerly:
The Importance of Vitamin D Testing
Naturally, vitamin D has many other benefits beside boosting immune function and protecting against respiratory diseases and viral infections. Wagner, for example, reviews some of the benefits in pregnancy and delivery, so for more information, be sure to listen to the interview.
As mentioned, the most important factor here is the level of vitamin D in your blood, not the daily dose, so it’s important to get tested at least twice a year. Again, you want a level of at least 40 ng/mL, and ideally between 60 ng/mL and 80 ng/mL.
According to data published in the Archives of Internal Medicine,
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Importantly, aside from people with darker skin, the elderly tend to lose the ability to synthesize vitamin D from sun exposure, and therefore tend to have suboptimal levels even if they spend plenty of time outdoors. “It's at that point people may need to supplement or find additional sources,” Baggerly says.
One of the easiest and most cost-effective ways of measuring your vitamin D level is to participate in the GrassrootsHealth’s personalized nutrition project, which includes a vitamin D testing kit, either alone or in combination with the omega-3 test. This is done in the convenience of your home.
You’ll learn your nutrient levels, how effective your health actions are, and you’ll be able to see 1000’s of other data sets that allow you to compare health outcomes important to you.
The Synergy Between Magnesium and Vitamin D
If your vitamin D level is low and remains low even though you’re taking high dosages every day, say around 5,000 to 10,000 IUs, you may be too deficient in magnesium for your body to convert the vitamin D into its active form. As explained by Hollis:
GrassrootsHealth now also has a magnesium research project called Magnesium* PLUS Focus, which is also open for enrollment. All of these nutrient field trial projects involve sending in a blood spot test that you do at home, and filling out a health questionnaire and providing details on the supplements you take.
COVID-19 Study Underway
Last but not least, GrassrootsHealth is currently working on a vitamin D study to assess its ability to prevent COVID-19 and/or reduce illness severity. Wagner explains:
REALLY IMPORTANT: Optimize Your Vitamin D Levels Before Fall!
Not only will be this an important strategy for you and your family, but it would be really helpful to start thinking about your community. People of color are at really high risk because their skin color impairs their ability to generate vitamin D from sun exposure. So if you could speak to any pastors in churches with large congregations of people of color and help them start a program getting people on vitamin D you could help save many lives, far more than any vaccine program.
Additionally, if you have a family member or know anyone who is in an assisted living facility you could meet with the director of the program and encourage them to get everyone tested or at least start them on vitamin D. Tomorrow I will have an article with more specific action steps, so you can start planning now.
For years, I’ve stressed the importance of optimizing your vitamin D level, especially in anticipation of flu season, and it seems clear it can go a long way toward protecting yourself against COVID-19 as well. Wagner notes:
In closing, experts are already warning that SARS-CoV-2 may reemerge in the fall when temperatures and humidity levels drop, thereby increasing the virus’ transmissibility. Now is the time to check your vitamin D level and start taking action to raise it if you’re below 60 ng/mL.
Again, an easy and cost-effective way of measuring your vitamin D level is to order GrassrootsHealth’s vitamin D testing kit and learn more about vitamin D and its impact on your health. Knowledge is empowerment, and that is particularly true during this pandemic.
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