Doctors Warn You Not to Take Too Much of This Vitamin Right Now

Leah Groth

May 15, 2021 at 8:14 AM·3 min read

Since the start of the pandemic, there have been multiple studies examining how vitamins can impact your chances of contracting COVID-19 and amping up on them may influence severity of infection and even death. However, a new study warns that one in particular may not be as effective as previously believed. Read on to find out what it is—and to ensure your health and the health of others, don't miss these Sure Signs You Caught COVID and Maybe Didn't Know It.

Can Vitamin D Help with COVID-19 Outcome?

Researchers from Brazil conducted a randomized, double-blind, placebo-controlled clinical trial (the gold standard in evaluating drug efficacy) involving 240 patients in a São Paulo City hospital in June-August 2020. They divided them into two groups, one of which was given a peanut oil solution and the other, D3 in a single dose dissolved into the same solution. They were all treated for COVID-19 with the same hospital protocol, given antibiotics and anti-inflammatory drugs. They found that vitamin D had no clinical outcome impact on the length of hospital stay, admission to ICU, intubation, or death.

There Is "No Indication" It Can Help with COVID

"In vitro studies or trials with animals had previously shown that in certain situations vitamin D and its metabolites can have anti-inflammatory and anti-microbial effects, as well as modulating the immune response. We decided to investigate whether a high dose of the substance could have a protective effect in the context of an acute viral infection, reducing either the inflammation or the viral load," Rosa Pereira, principal investigator for the project, told Agência FAPESP, per a press release, about the study published in Journal of the American Medical Association (JAMA). "So far we can say there's no indication to administer vitamin D to patients who come to the hospital with severe COVID-19," she said.

Bruno Gualano, a researcher at FM-USP and penultimate author of the article, explains that the findings mean there is no "silver bullet" for the treatment of COVID-19. "But that doesn't mean continuous use of vitamin D can't have beneficial effects of some kind," he said.

How Much Vitamin D Should You Take?

While vitamin D is essential, taking more than the recommended dose can result in toxicity, also called hypervitaminosis. Per the Mayo Clinic, it can cause a buildup of calcium in your blood (hypercalcemia), resulting in symptoms such as nausea and vomiting, weakness, and frequent urination. "Vitamin D toxicity might progress to bone pain and kidney problems, such as the formation of calcium stones," they explain.

Taking 60,000 international units (IU) a day of vitamin D for several months has been shown to cause toxicity. "This level is many times higher than the U.S. Recommended Dietary Allowance (RDA) for most adults of 600 IU of vitamin D a day," they explain.

Should You Take Vitamin D at All?

"If you are deficient in vitamin D, that does have an impact on your susceptibility to infection. So I would not mind recommending, and I do it myself taking vitamin D supplements," Dr. Anthony Fauci said during an Instagram Live with actress Jennifer Garner. Talk to your doctor to see if it's right for you. And to protect your health, don't miss these Signs You're Getting One of the "Most Deadly" Cancers.