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Can Vitamin D Help Improve COVID-19 Survival Rates?

Can Vitamin D Help Improve COVID-19 Survival Rates?

As of now, there is still no cure or vaccine for COVID-19. Although institutions are working hard to develop them right away, there’s no guarantee that they will be ready soon. Because of this, we need to maximize the potential of vitamins and minerals in fighting the virus. One vitamin that medical experts are looking into is vitamin D. Is there a connection between COVID-19 and vitamin D deficiency?

What is Vitamin D?

Before we talk about the connection between COVID-19 and vitamin D deficiency, let us first introduce the vitamin. Growing up, we learned that we can get vitamin D from being exposed to sunlight. This is because our body (particularly the cholesterol in the skin) produces vitamin D upon exposure to the sun. Vitamin D, like other vitamins, regulates a lot of bodily functions. However, it plays a bigger role in calcium absorption. Therefore, it is important for healthy, strong bones.

Background on COVID-19 and Vitamin D Deficiency

Various reports indicate that people are now interested in stocking up on vitamin D. If it is important for healthy bones, then what is the relationship between COVID-19 and Vitamin D deficiency?

The idea that COVID-19 and vitamin D deficiency are connected first came in February 2020. It was when two researchers from the China Medical University made extensive research about possible “out-of-the-box approaches” to help fight the virus.

The researchers, Lei Zhang and Yunhui Liu, focused their study on the use of vitamins and minerals. They discovered that the novel coronavirus affected the populations of house-bound people, institutionalized patients, elderlies in nursing homes, and prisoners. Generally, these people were in places where they could not get enough vitamin D. In conclusion, they believe that “vitamin D could work as another therapeutic option…”

Since then, has there been newer, more clinically-based research released about the correlation between COVID-19 and vitamin D deficiency?

There is.

A research team, led by Vadim Backman from Northwestern University, studied the data from 10 countries affected by the coronavirus. The countries included in the research were Spain, Italy, Switzerland, Germany, South Korea, China, Iran, France, the UK, and the US. They found that countries with a high number of incidences and deaths also experienced vitamin D deficiency.

The Latest Studies About COVID-19 and Vitamin D Deficiency

According to Backman, they compared the countries using various metrics, like the healthcare systems, age groups, and even testing rates. He said that none of them seem to play a significant role when it comes to the difference in the incidence and mortality rates. For example, Italy has the best healthcare system, yet it also had a lot of mortalities.

On the argument that it is probably because of the age of the patients, Backman countered that they also checked the death rates between the same age groups. There were still differences, he said. For instance, they checked the countries and analyzed the death rates between patients of the same age group. They noted that countries with vitamin D deficiency still had more incidences and deaths. This led the researchers to believe that it may be due to vitamin D deficiency.

What Happens to Patients with COVID-19 and Vitamin D Deficiency?

Backman explained that patients with COVID-19 often die because of the cytokine storm. Cytokine storm is a hyperinflammatory condition caused by an overactive immune system. Because of the inflammation, cytokine storms can severely damage the lungs. It can also cause acute respiratory syndrome. If the condition is not managed, it may lead to death.

Vitamin D prevents the immune system from being too active and therefore, can prevent the deadly cytokine storm. Subsequently, patients with COVID-19 and vitamin D deficiency can develop an overactive immune system and cytokine storm.

As a conclusion, Backman and his team shared that enough vitamin D can “cut the mortality rate in half” among COVID-19 patients.

Other Investigations That Show Vitamin D’s Potential

In one investigation involving 489 participants, scientists identified that people who were likely vitamin D deficient were almost two times more at risk of testing positive for COVID than the participants who were likely vitamin D sufficient.

Another study published in December of 2020 also stated in their discussion that vitamin D may be “may be an effective, well-tolerated, and easily and immediately accessible treatment for COVID-19.” The researchers also mentioned that vitamin D shows potential in mitigating the SARS-CoV2 virus.

COVID-19 and Vitamin D Deficiency in the Philippines

A researcher, Mark Alipio, from the Philippines also did research about COVID-19 and vitamin D deficiency. He divided the patient participants into 4 categories based on the symptoms experienced. The categories were mild, ordinary, severe, and critical. Additionally, he also checked their vitamin D level in the blood. At the end of the study, Alipio noted that there was an “increasing odds ratio” of having mild symptoms when a patient has a high vitamin D level.

This led Alipio to conclude that vitamin D supplementation can help in treating the COVID-19 infection.

The Safe Ways to Get Enough Vitamin D

Although there are no studies to prove that vitamin D can prevent COVID-19 infection, it remains to be an important vitamin. There are three safe ways to get vitamin D to promote health:

  • Sun exposure. Go outside, preferably in the morning, for 15-20 minutes. You do not have to do it every day. Experts suggest that 3 days a week are enough.
  • Eating tuna, salmon, and other fatty fish. These are great sources of vitamin D. There are also products like milk and yogurt that are fortified with vitamin D.
  • Food supplements. Of course, you can talk to your doctor about a good food supplement with vitamin D.

Reminders About COVID-19 and Vitamin D Deficiency

Although there are promising studies about vitamin D and COVID-19, do not jump into taking supplements right away. Excessive intake of vitamin D can lead to toxicity. This will result to harmful calcium buildup. Vitamin D toxicity can also cause bone pain and kidney problems. For supplements, be sure to consult your doctor.

Key Takeaways on COVID-19 and Vitamin D Deficiency

The results in research about COVID-19 and vitamin D deficiency are promising. For this reason, you may want to go outside and get enough sunlight.

Hello Health Group does not provide medical advice, diagnosis or treatment.


Can Vitamin D Prevent COVID-19?,, Accessed 05 June 2020

Vitamin D levels appear to play role in COVID-19 mortality rates,, Accessed 05 June 2020

Paging Dr. Hamblin: Does Vitamin D Help Fight COVID-19?,, Accessed 05 June 2020

Vitamin D Deficiency,–vitamin-d-deficiency, Accessed 05 June 2020

Vitamin D,, Accessed 05 June 2020

Vitamin D supplementation could possibly improve clinical outcomes of patients infected with Coronavirus-2019 (COVID2019),, Accessed 05 June 2020

Covid-19 and high-dose Vitamin D supplementation TRIAL in high-risk older patients (COVIT-TRIAL): study protocol for a randomized controlled trial,, Accessed April 19, 2021

Association of Vitamin D Status and Other Clinical Characteristics With COVID-19 Test Results,, Accessed April 19, 2021

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Written by Lorraine Bunag, R.N. Updated Apr 19
Fact Checked by Hello Doctor Medical Panel