Can Vitamin D Cure COVID-19?

Vitamin D is one of the essentials for strong bones, but what many may not know is that its impact on immune system is also as important.

But, could it also play a role in lowering your risk of contracting or developing severe COVID-19?

How vitamin D helps with immune system

Vitamin D regulates the body's response and reduces harmful inflammation. Research has proven that it enhances the function of T cells and macrophages—immune cells. These cells are known to combat pathogens effectively.

Low vitamin D levels are also linked to an increased susceptibility to respiratory infections like tuberculosis, asthma, and chronic obstructive pulmonary disease (COPD). Whereas sufficient vitamin D is known to promote a better lung health.

A study that analyzed 11,321 participants across 14 countries showed that supplementing with vitamin D reduced the risk of acute respiratory infections by 12%, with the most significant benefit seen in those who were deficient.

So, will it also work and protect against COVID-19?

Reducing Respiratory Risks: Vitamin D supplementation is known to bolster immune defense, which could mitigate the severity of respiratory infections, including those caused by SARS-CoV-2.

Cytokine Storm Prevention: Vitamin D may help regulate cytokine activity. These are proteins that are essential for the immune system. A "cytokine storm," that happens due to excessive pro-inflammatory cytokine release, is a hallmark of severe COVID-19. It is seen and has been analyzed in studies that those with COVID-19 produce these proteins that lead to a "cytokine storm", which is immune system's natural response. This has also been seen in complications like acute respiratory distress syndrome (ARDS). Studies have found that vitamin D deficiency could exacerbate these immune responses, while supplementation might help counter them.

At this point, there are clincal trials, which are investigating the effects of vitamin D supplementation (dosages up to 200,000 IU) in people with COVID-19.

Who’s Most at Risk of Vitamin D Deficiency?

Vitamin D deficiency is widespread, especially among:

• Older adults are most vulnerable to severe COVID-19 outcomes.
• People who are not often exposed to sun, or people with darker complexion, as their body produces less vitamin D naturally.
• Those who are overweight or have issues with weight management may also have the risk of being vitamin D deficient, as it throws off the body's natural vitamin D metabolism.

A vitamin deficiency could make you more susceptible to infections and poor immune responses. So what can be done instead? Experts recommend testing your blood levels, particularly during the winter months, when natural synthesis from sunlight is minimal.

What is healthy and what is not?

Too much or too little of anything is not good for your health. Thus, there are levels of how much vitamin D should one maintain. Maintaining vitamin D levels between 30–60 ng/mL is ideal for immune health, and is accepted by most healthcare professionals too. For many, a daily dose of 1,000–4,000 IU is sufficient, but individuals with deficiencies may require higher amounts under medical supervision.

Supplementation, when combined with other preventive measures like vaccination, proper hygiene, and mask-wearing, can enhance overall immunity.

Best Sources of Vitamin D

As per the British Heart Foundation: The best food sources of vitamin D are oily fish, including salmon, mackerel, and sardines. Other sources include egg yolks, red meat, and liver. Vitamin D is added to some foods too, including breakfast cereals, plant milks and fat spreads. Check information on-pack to see if this applies to the products you buy.