Vitamin D may lower risk of contracting COVID-19, says new research

A series of recent studies found that people with healthy levels of vitamin D were less likely to contract COVID-19 and suffer severe complications from it.

​Vitamin D

Vitamin D supplement

Credit: ExQuisine via Adobe Stock
  • Vitamin D is known to play a role in healthy immune system function.
  • If further research confirms that vitamin D may help prevent people from contracting COVID-19, it could become a relatively cheap and scalable strategy to stop the spread of the virus.
  • You can get vitamin D through sunlight, diet, supplements, and prescription.

Vitamin D deficiency is surprisingly common in the U.S., affecting about 42 percent of the population. Studies have linked low levels of vitamin D (which is actually a hormone, not a vitamin) to fatigue, muscle and bone pain, bone and hair loss, weakened immune system, dry skin, and depression.

Now, new research suggests that vitamin D deficiency may also increase the odds of contracting and suffering more severe complications from COVID-19.

One study, published September 25 in PLoS ONE, tracked the health of 235 patients in Iran who had contracted COVID-19. After controlling for confounding variables, the researchers found a significant association between vitamin D deficiency and more severe COVID-19 complications, including death.

The researchers wrote that patients who had healthy levels of vitamin D "had a lower risk of becoming unconscious and becoming hypoxic."

"Patients who were vitamin D sufficient had significantly lower blood levels of the inflammatory marker CRP and had a higher total blood lymphocyte count suggesting that vitamin D sufficiency had improved the immune function in these patients and raising the inflammatory markers," the researchers wrote. "This beneficial effect on the immune system may also reduce the risk of acquiring this insidious potentially life-threatening viral infection."

'Inexpensive, safe and scalable'

A second study, published in the October edition of The Journal of Steroid Biochemistry and Molecular Biology, found that hospitalized COVID-19 patients who were given a high dose of Calcifediol (a metabolite the body produces from vitamin D) experienced less severe complications than other patients who received similar care, but not Calcifediol.

Of the 50 patients who received Calcifediol, none died, but two of the 26 patients who didn't receive the metabolite did.

"Calcifediol seems to be able to reduce severity of the disease," the researchers wrote. "But larger trials with groups properly matched will be required to show a definitive answer."

The two studies were published in the wake of a retrospective study, published September 3 in JAMA, that analyzed 489 people who were tested for COVID-19 by UChicago Medicine. All of those people had also had their vitamin D levels tested within the past year. The study found that people with an untreated vitamin D deficiency were nearly twice as likely to test positive for COVID-19.

David Meltzer, Chief of Hospital Medicine at UChicago Medicine and lead author of the study, said that while the results don't establish causation, the relationship is worth studying further.

"Understanding whether treating vitamin D deficiency changes COVID-19 risk could be of great importance locally, nationally and globally," Meltzer told UChicago News. "Vitamin D is inexpensive, generally very safe to take, and can be widely scaled."

But despite the growing body of evidence linking vitamin D deficiency with more severe COVID-19 outcomes, it's important to note that scientists still don't fully understand how vitamin D interacts with COVID-19.

"There is biological plausibility for benefit of vitamin D, since it is known to regulate innate and adaptive immunity in ways that might reduce the viral load in patients exposed to SARS-CoV-2 and mitigate the severity and consequences of cytokine storm," Dr. Michael Lewiecki, of the University of New Mexico School of Medicine in Albuquerque, told Medscape.

"However, it is important to recognize that associations reported in observational studies do not necessarily mean there is a causal relationship. It may be that higher vitamin D is a marker of better health and lower baseline risk of complications of COVID-19."

Healthy levels of vitamin D

Although there's debate on the importance of vitamin D levels, it's probably a good idea to make sure you're not deficient in vitamin D. A healthy range is generally considered to be between 20 and 50 nanograms per milliliter of blood (though certain populations may require higher levels).

You can get more vitamin D by spending time in sunlight; eating fatty fish, egg yolks, mushrooms and fortified foods; taking supplements (note the differences between vitamin D2 and vitamin D3); or getting a doctor's prescription for a specific type of vitamin D.

But note that consuming too much vitamin D can be toxic, as the National Institutes of Health warns:

"The daily upper limit for vitamin D is 25 mcg to 38 mcg (1,000 to 1,500 IU) for infants; 63 mcg to 75 mcg (2,500 to 3,000 IU) for children 1-8 years; and 100 mcg (4,000 IU) for children 9 years and older, adults, and pregnant and lactating teens and women. Vitamin D toxicity almost always occurs from overuse of supplements."

This is what aliens would 'hear' if they flew by Earth

A Mercury-bound spacecraft's noisy flyby of our home planet.

Image source: sdecoret on Shutterstock/ESA/Big Think
Surprising Science
  • There is no sound in space, but if there was, this is what it might sound like passing by Earth.
  • A spacecraft bound for Mercury recorded data while swinging around our planet, and that data was converted into sound.
  • Yes, in space no one can hear you scream, but this is still some chill stuff.

First off, let's be clear what we mean by "hear" here. (Here, here!)

Sound, as we know it, requires air. What our ears capture is actually oscillating waves of fluctuating air pressure. Cilia, fibers in our ears, respond to these fluctuations by firing off corresponding clusters of tones at different pitches to our brains. This is what we perceive as sound.

All of which is to say, sound requires air, and space is notoriously void of that. So, in terms of human-perceivable sound, it's silent out there. Nonetheless, there can be cyclical events in space — such as oscillating values in streams of captured data — that can be mapped to pitches, and thus made audible.


Image source: European Space Agency

The European Space Agency's BepiColombo spacecraft took off from Kourou, French Guyana on October 20, 2019, on its way to Mercury. To reduce its speed for the proper trajectory to Mercury, BepiColombo executed a "gravity-assist flyby," slinging itself around the Earth before leaving home. Over the course of its 34-minute flyby, its two data recorders captured five data sets that Italy's National Institute for Astrophysics (INAF) enhanced and converted into sound waves.

Into and out of Earth's shadow

In April, BepiColombo began its closest approach to Earth, ranging from 256,393 kilometers (159,315 miles) to 129,488 kilometers (80,460 miles) away. The audio above starts as BepiColombo begins to sneak into the Earth's shadow facing away from the sun.

The data was captured by BepiColombo's Italian Spring Accelerometer (ISA) instrument. Says Carmelo Magnafico of the ISA team, "When the spacecraft enters the shadow and the force of the Sun disappears, we can hear a slight vibration. The solar panels, previously flexed by the Sun, then find a new balance. Upon exiting the shadow, we can hear the effect again."

In addition to making for some cool sounds, the phenomenon allowed the ISA team to confirm just how sensitive their instrument is. "This is an extraordinary situation," says Carmelo. "Since we started the cruise, we have only been in direct sunshine, so we did not have the possibility to check effectively whether our instrument is measuring the variations of the force of the sunlight."

When the craft arrives at Mercury, the ISA will be tasked with studying the planets gravity.

Magentosphere melody

The second clip is derived from data captured by BepiColombo's MPO-MAG magnetometer, AKA MERMAG, as the craft traveled through Earth's magnetosphere, the area surrounding the planet that's determined by the its magnetic field.

BepiColombo eventually entered the hellish mangentosheath, the region battered by cosmic plasma from the sun before the craft passed into the relatively peaceful magentopause that marks the transition between the magnetosphere and Earth's own magnetic field.

MERMAG will map Mercury's magnetosphere, as well as the magnetic state of the planet's interior. As a secondary objective, it will assess the interaction of the solar wind, Mercury's magnetic field, and the planet, analyzing the dynamics of the magnetosphere and its interaction with Mercury.

Recording session over, BepiColombo is now slipping through space silently with its arrival at Mercury planned for 2025.

Learn the Netflix model of high-performing teams

Erin Meyer explains the keeper test and how it can make or break a team.

  • There are numerous strategies for building and maintaining a high-performing team, but unfortunately they are not plug-and-play. What works for some companies will not necessarily work for others. Erin Meyer, co-author of No Rules Rules: Netflix and the Culture of Reinvention, shares one alternative employed by one of the largest tech and media services companies in the world.
  • Instead of the 'Rank and Yank' method once used by GE, Meyer explains how Netflix managers use the 'keeper test' to determine if employees are crucial pieces of the larger team and are worth fighting to keep.
  • "An individual performance problem is a systemic problem that impacts the entire team," she says. This is a valuable lesson that could determine whether the team fails or whether an organization advances to the next level.
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Photo by Martin Adams on Unsplash
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