What about COVID-19 and vitamin D?

Long-time readers know that my “go-to” sources for natural medicines (herbs, vitamins, and supplements) are ConsumerLab.com and Natural Medicines(TM). ConsumerLab has posted about coronavirus and vitamin D:

Vitamin D supplements, taken daily in moderate doses, may help to reduce the risk of respiratory infections and viruses such as influenza A in children and adults who are deficient (< 20 ng/mL) or severely deficient (< 10 ng/mL) in vitamin D. 

Although there is not currently any research suggesting vitamin D supplements decrease the risk of coronavirus infection specifically, maintaining an adequate blood level of vitamin D (25OH vitamin D, 20 to 30 ng/mL) by consuming vitamin D-fortified products (such as most milks, certain other dairy foods, and some plant-based milks), or taking a vitamin D supplement is a good, safe, preventative measure for protecting against respiratory infections in general.

To maintain healthy vitamin D levels, only 400 to 800 IU (15 to 20 mcg) of vitamin D3 is required daily, but, to boost low levels, higher doses, such as 2,000 IU daily, are used and are generally safe.

Very large doses of vitamin D, which have been taken periodically (such as 100,000 IU vitamin D2 taken monthly) may not be as helpful and could even increase the risk of respiratory infections in some people. 

There are many vitamin D supplements on the market. ConsumerLab has tested a wide variety and has published its Top Picks in its Vitamin D Supplements Review, which contains additional information about using vitamin D, as well as its benefits, dosing, and potential side effects. 

Of course, the most important thing you can do to avoid infection with coronavirus is to prevent exposure by following the latest recommendations of the CDC and World Health Organization and take steps to stay healthy, including getting adequate sleep, keeping up with your daily exercise, and eating a healthy nutritious diet. 

© Copyright WLL, INC. 2020. This blog provides a wide variety of general health information only and is not intended to be a substitute for professional medical advice, diagnosis, or treatment from your regular physician. If you are concerned about your health, take what you learn from this blog and meet with your personal doctor to discuss your concerns.

5 thoughts on “What about COVID-19 and vitamin D?

  • Roger,

    The quote to which you are likely referring is, as I indicate, from ConsumerLab, not me. They say, “… maintaining an adequate blood level of vitamin D (25-OH vitamin D, 20 to 30 ng/mL) … is a good, safe, preventative measure for protecting against respiratory infections in general.” They use these levels for this indication as that’s what the studies show.

    Obviously, not all agree. “Endocrine News,” likely a group that “has a clue,” carried an article stating, “Three endocrinologists interviewed for an Endocrine News article on osteoporosis in the April issue all aimed for levels of at least 30 ng/ml — with an eye toward maximizing bone health in at-risk patients. Holick believes that maintaining a level of 40 to 60 ng/ml is desirable in the general population and a level up to 100 ng/ml is ‘perfectly safe.’ Others urge caution about going above 50 ng/ml. ‘The data are not clear cut, but some evidence of toxicity has been associated with levels above 50 ng/ml, including hypercalcemia and kidney stones,’ says Clifford Rosen, MD, director of clinical and translational research at the Maine Medical Center Research Institute, who worked on the IOM guideline.’ But even a level of 50 ng/ml leaves a lot of leeway above the IOM’s deficiency level of 20 ng/ml and the Endocrine Society’s sufficiency level of 30 ng/ml. And it leaves a lot of leeway for taking supplements — the IOM guideline found that intakes as high as 4,000 IU/day should be safe for adults, although longterm risks of such high intakes are unknown.”

    The Doctors of Pharmacology at “Prescribers’ Letter” and the “Natural Medicines Comprehensive Database” both say, “Optimal blood levels of 25-hydroxyvitamin D for maintaining bone density is 30-100 ng/mL” The American Geriatric Society (AGS) expert panel concluded: “Based on all the evidence, at a minimum, we recommend vitamin D levels of 30 ng/mL, and because of the vagaries of some of the assays, to guarantee sufficiency, we recommend between 40 and 60 ng/mL for both children and adults.” AGS adds, “There are no recorded cases of vitamin D intoxication at serum levels less than 200 ng/mL.”

    Of 25-OH vitamin D levels, Mayo Clinic says, “20-50 ng/mL = optimum levels, 51-80 ng/mL = increased risk of hypercalciuria), and >80 ng/mL = toxicity possible,” adding, “80 ng/mL is the lowest reported level associated with toxicity in patients without primary hyperparathyroidism who have normal renal function. Most patients with toxicity have levels >150 ng/mL.”

    So, people “with a clue” have a variety of interpretations of the data. For me and my practice partners, when monitoring vitamin D supplementation, we aim for a 25-OH vitamin D level of 40 and 60 ng/mL for most children and adults. For adults aware of the risks that want to aim for 60-100 ng/ml, we’re happy to go along with that also.

    I hope you find this helpful.

    Dr. Walt

  • Roger,

    The quote to which you are likely referring is, as I indicate, from ConsumerLab, not me. They say, “… maintaining an adequate blood level of vitamin D (25-OH vitamin D, 20 to 30 ng/mL) … is a good, safe, preventative measure for protecting against respiratory infections in general.” They use these levels for this indication as that’s what the studies show.

    Obviously, not all agree. “Endocrine News,” likely a group that “has a clue,” carried an article stating, “Three endocrinologists interviewed for an Endocrine News article on osteoporosis in the April issue all aimed for levels of at least 30 ng/ml — with an eye toward maximizing bone health in at-risk patients. Holick believes that maintaining a level of 40 to 60 ng/ml is desirable in the general population and a level up to 100 ng/ml is ‘perfectly safe.’ Others urge caution about going above 50 ng/ml. ‘The data are not clear cut, but some evidence of toxicity has been associated with levels above 50 ng/ml, including hypercalcemia and kidney stones,’ says Clifford Rosen, MD, director of clinical and translational research at the Maine Medical Center Research Institute, who worked on the IOM guideline.’ But even a level of 50 ng/ml leaves a lot of leeway above the IOM’s deficiency level of 20 ng/ml and the Endocrine Society’s sufficiency level of 30 ng/ml. And it leaves a lot of leeway for taking supplements — the IOM guideline found that intakes as high as 4,000 IU/day should be safe for adults, although longterm risks of such high intakes are unknown.”

    The Doctors of Pharmacology at “Prescribers’ Letter” and the “Natural Medicines Comprehensive Database” both say, “Optimal blood levels of 25-hydroxyvitamin D for maintaining bone density is 30-100 ng/mL” The American Geriatric Society (AGS) expert panel concluded: “Based on all the evidence, at a minimum, we recommend vitamin D levels of 30 ng/mL, and because of the vagaries of some of the assays, to guarantee sufficiency, we recommend between 40 and 60 ng/mL for both children and adults.” AGS adds, “There are no recorded cases of vitamin D intoxication at serum levels less than 200 ng/mL.”

    Of 25-OH vitamin D levels, Mayo Clinic says, “20-50 ng/mL = optimum levels, 51-80 ng/mL = increased risk of hypercalciuria), and >80 ng/mL = toxicity possible,” adding, “80 ng/mL is the lowest reported level associated with toxicity in patients without primary hyperparathyroidism who have normal renal function. Most patients with toxicity have levels >150 ng/mL.”

    So, people “with a clue” have a variety of interpretations of the data. For me and my practice partners, when monitoring vitamin D supplementation, we aim for a 25-OH vitamin D level of 40 and 60 ng/mL for most children and adults. For adults aware of the risks that want to aim for 60-100 ng/ml, we’re happy to go along with that also.

    I hope you find this helpful.

    Dr. Walt

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