Vitamin D for Fighting Coronavirus

Vitamin D calls to mind sunshine and tall glasses of cold milk, and for good reasons. Exposure to sunlight and drinking milk are both ways to get vitamin D. Vitamin D has long been known as a requirement for strong, healthy bones, but news from the front lines of the fight against COVID-19 has revealed new uses for vitamin D supplementation: fighting coronavirus and other viral respiratory illnesses.

As recently as 2017, researchers at Queen Mary University of London published research showing that supplementation with vitamin D helps prevent respiratory infections like the common cold and influenza. Other studies came to a similar conclusion, while additional research indicates that for the coronavirus found in COVID-19, vitamin D supplementation is more helpful in reducing the harm caused by coronavirus, rather than preventing it.  

What Are Vitamins? 

Vitamins are chemical compounds that are required for good health. Our bodies can make some vitamins, but others we can't make or cannot generate in the quantities we need. Some vitamins, like vitamin C, are water-soluble. They dissolve in water and are easily passed out of the body through urine.  Vitamins like vitamin D are fat soluble, meaning they are carried and stored in the body's fatty tissues. Although we can generate a little vitamin D from exposure to intense sunlight, it's not enough for optimum health. In fact, vitamin D deficiency is one of the most common maladies in the world. It’s also a problem for otherwise healthy adults in the USA. Getting enough vitamin D requires supplementation for the best health outcomes. 

How Does Vitamin D Help the Body Fight Viruses? 

Vitamin D, particularly D3, also known as calciferol, helps the body absorb minerals such as magnesium, phosphate, and calcium. These minerals are required for thousands of processes in the body. Among those many processes are those of the immune system, which helps us fight infections. 

Vitamin D’s role in the good health proper working of the immune system involves reducing and modulating inflammation, as well as increasing the production of protein-like molecules in the lungs called peptides. In humans and other primates, an entire class of virus and bacteria-fighting peptides are only activated when sufficient levels of vitamin D are present. No other kinds of animals enjoy this potent weapon against acute respiratory infections.  

What about Vitamin D and Coronavirus?   

Research has consistently shown that people who have the worst outcomes from being infected with SARS-CoV-2 (COVID-19) have dangerously low levels of vitamin D. Researchers think that without enough vitamin D, the virus-fighting peptides we discussed previously never form, or if they do, they do so in far lower levels than needed. Although the mechanisms by which vitamin D activates COVID-19 fighting peptides are extremely complex, we can all understand this equation: people who have significant deficiencies in vitamin D never realize the benefits of these potent infection-fighters. 

COVID-19, Vitamin D, and Inflammation 

There’s another way that vitamin D levels affect outcomes in COVID-19, and that’s inflammation. Inflammation is a primary response of the immune system. The right amounts of inflammation can help fight serious infections, like COVID-19.  A healthy level of vitamin D is essential for the immune system’s ability to produce just the right amount of inflammation to fight viruses. However, in people with a severe vitamin D deficiency, the immune system can overreact, producing extreme hyper-inflammation, which leads to a cytokine storm. Cytokine storms can easily be lethal. 

Cytokines are protein-like compounds that make up one type of immune response to viral and bacterial infection. The immune system can generate different cytokines that govern many kinds of disease-fighting response, but as with everything else, too much is a bad thing. With a poorly controlled immune response, excessive cytokines treat the body’s own cells as foreign invaders, killing tissue and causing dangerous inflammation of the body’s blood vessels and organs. This leads to serious organ damage, with the kidneys, lungs, liver, and blood vessels being most commonly affected. Death from multiple organ failure is the result. 

Medical researchers have successfully reduced inflammation and improved cytokine performance in several illnesses by adding vitamin D supplementation. There's good evidence that using vitamin D supplements during infection with COVID-19 prevents hyper-inflammation and reduces the risk of a cytokine storm. 

There’s more evidence that low vitamin D levels correlate with poor outcomes in COVID-19 infection. We know that older people have a much higher risk of developing severe or lethal illness from contracting COVID-19. We also know that as we age, our ability to synthesize vitamin D drops significantly and vitamin D deficiency is common in the elderly. 

There isn’t enough evidence yet to say if adding vitamin D supplements can prevent an infection by coronavirus, but we do know that low levels of vitamin D are associated with less favorable outcomes, including respiratory failure, organ failure, and death. In fact, research has shown that around 80% of all COVID-19 patients that suffered acute respiratory failure had severe vitamin D deficiency.