There's even more evidence that getting enough vitamin D could reduce the risk of severe coronavirus infections
There's even more evidence that getting enough vitamin D could help prevent severe coronavirus infection, particularly in older people.
Having adequate levels of vitamin D is linked to lower risk of dangerous complications of COVID-19, including low oxygen levels, unconsciousness, and death, according to a study published September 25 in PLOS ONE.
Researchers from Boston University School of Medicine and Tehran University of Medical Studies took blood samples from 235 patients admitted to the Sina Hospital in Tehran, Iran with coronavirus infection. The researchers tracked the patients' outcomes, and analyzed their blood for vitamin D levels, as well as markers of inflammation and lymphocytes, white blood cells that help fight infection.
They found that patients with sufficient vitamin D, or levels above a clinical deficiency, were less likely to have severe infections and difficulty breathing. They were also less prone to cytokine storms, aggressive immune responses linked to high levels of inflammation that can be deadly.
Overall, patients with enough vitamin D were more likely to survive. This was particularly true for patients over 40, who were 50% less likely to die if they had adequate vitamin D levels, according to the research.
The study's author has ties to the supplement industry
Dr. Michael F. Holick, co-author of the study and a professor of medicine at Boston University School of Medicine, has long been a proponent of vitamin D for preventing disease, and in a 2017 paper said that rampant vitamin D deficiency is a "pandemic" that affects over a billion people worldwide.
"Because vitamin D deficiency and insufficiency is so widespread in children and adults in the United States and worldwide, especially in the winter months, it is prudent for everyone to take a vitamin D supplement to reduce risk of being infected and having complications from COVID-19," Holick said in a press release.
However, Holick has previously faced criticism for profiting from his research on vitamin D by working with supplement companies. A New York Times investigation in 2018 found that Holick received $163,000 for consulting with pharmaceutical companies from 2013 to 2017, and even more money to fund his research.
However, there's still evidence vitamin D is important for immune health
Despite the possible conflict of interest, Holick's newest study is supported by previous research with similar conclusions. Extensive evidence has linked vitamin D deficiency to greater risk of infection, particularly from respiratory diseases like COVID-19.
While the findings are somewhat contentious, since researchers don't fully understand if vitamin D supplements can cause better health outcomes, studies have consistently linked vitamin D deficiency to greater risk of severe infection.
Even Dr. Anthony Fauci, the leading infectious disease expert in the US, said he takes vitamin D and acknowledges it's one of the few supplements that might be helpful for a strong immune system.
And many people are deficient in vitamin D, especially while sheltering indoors or in darker winter months, since our bodies naturally produce the nutrient in response to sunlight.
People with darker skin may be particularly susceptible, since melanin can slow the process of producing vitamin D.
So, while vitamin D isn't a cure-all, and too much can have serious side effects, there's good evidence that it's a healthy choice to get enough of the nutrient, whether through sunlight, supplements, or in your diet with foods like eggs, fish, liver, and mushrooms.
Read more:
FOLLOW US: Insider is on Facebook.