Does Vitamin D Help Us Fight Infections? A Discussion with Dr. Vatsal Thakkar

As COVID-19 continues to rage across the globe, everyone has been trying to figure out how to protect themselves from getting infected. People wear masks, avoid gatherings, travel, and work from home to prevent the disease. We also know that there is a lot of discussion about COVID and what are the correct measures and what we should do which we have talked about on this show here, here, and here. Although we know a lot about what puts people at risk (age, diabetes, heart disease), not much is talked about as far as preventative care goes. That might be where we should begin our discussion about vitamin D. Perhaps this common vitamin is a linchpin to preventing severe disease and maintaining immunological health.

Where Does Vitamin D Work?

My guest today is Dr. Vatsal Thakkar, who is has written extensively on vitamin D deficiency in prominent publications like the Wall Street Journal. Evidence continues to mount showing that the fat soluble vitamin is involved in all sorts of biological processes in our body. Most know that vitamin D is necessary to regulate calcium levels and prevent osteoporosis. However, new research shows that it is critical to our immune function. Vitamin D works on immune cells to modulate our immune response to infections. It provides a dampening effect on the response to prevent an over-reaction of inflammatory chemicals which lead to conditions like cytokine storm.

Vitamin D also works to regulate fibrinogen which is a key substance in the clotting process. Without vitamin D, we can enter a slightly hypercoaguable state (too much clotting) which can put many of our organs at risk of damage. This could be seen with strokes or pulmonary emboli (clots to the lung causing breathing difficulty or death). Both cytokine storm and clotting disorders are important stages of severe COVID-19 infections that lead to significant death and disability.

From Where Does Vitamin D Come?

Vitamin D is an extremely common fat soluble vitamin that is most commonly produced in our bodies when exposed to UVB sunlight. We can also obtain the vitamin from consuming it in our diet, although, it is fairly uncommon to get enough unless you have a diet very high in fish. Thousands of years ago, humans spend the majority of their days outside in the sun hunting for food or growing it. Vitamin D was plentiful and we suspect few people were deficient.

Today, we spend most of our days indoors and spend very little time in the sun when the UVB light is most prevalent - the middle of the day. Once the sun goes down, the atmosphere filters out UVB light so any sunlight we obtain is unable to convert to vitamin D. Also, those living above the 35 parallel will not get any vitamin D converting sunlight for months during winter. So even sun exposure on a warm day in November won't be of any use for boosting our vitamin D levels.

What Is Vitamin D Deficiency?

Vitamin D deficiency is simply a condition where you have levels of vitamin D so low that your biological functions don't work as well as they should. Most people in the world are vitamin D deficient at least during part of the year. An insufficiency is usually defined as a blood level of below 30 ng/mL and a deficiency is less than 20 ng/mL. An insufficiency or deficiency puts you at risk for all the above described conditions. Those highest at risk for a deficiency are people with darker skin, low sun exposure, winter time, and live at higher latitudes.

How Do You Prevent & Fix a Vitamin D Deficiency?

Fortunately, preventing and fixing a deficiency is simple and inexpensive. Appropriate vitamin D levels can be achieved simply by daily supplementation. The authors at VitaminDforAll.org recommend 4000 IU daily and if someone is extremely deficient to take 10,000 IU per day for two weeks until a proper blood level is obtained. Fortunately, vitamin D is an inexpensive supplement.

Why Should We Care About Vitamin D?

So the big question is why do we care whether people have a deficiency in vitamin D? This is where today's guest explains that there are two different studies (one placebo controlled, the other not) which showed a dramatic difference in ICU admissions from those treated with vitamin D to those who weren't. In a Spanish study, nearly all the patients were vitamin D deficient on admission for COVID-19 those treated aggressively with vitamin D showed a 90% reduction in admission to the ICU.

Essentially, vitamin D deficiency is extremely common, simple and inexpensive to treat, and poses very low risks as an intervention. It is also something that everyone can do so that if they get infected with SARS-CoV-2 they will be less likely to get as sick. It is a simple intervention that may have profound effects on the overall mortality and morbidity of this virus.