vitamin D and COVID

At prohealthyx we care about the health of our clients, readers and followers. In these difficult times, exercising is key to maintain general health. However, a solid nutrition sets the fundaments to stay healthy, fit and strong. My clients know that when I develop a plan, macronutrients (proteins, fat and carbohydrates) are as important as micronutrients (mineral and vitamins). Amongst this latter, Vitamin D is common supplementation I advice.

What is vitamin D?

Vitamin D is essential for strong bones, because it helps the body use calcium from the diet. Traditionally, vitamin D deficiency has been associated with rickets, a disease in which the bone tissue doesn’t properly mineralize, leading to soft bones and skeletal deformities. But increasingly, research is revealing the importance of vitamin D in protecting against a host of health problems.

There are newly appreciated associations between vitamin D insufficiency and many other diseases, including tuberculosis, psoriasis, multiple sclerosis, inflammatory bowel disease, type-1 diabetes, high blood pressure, increased heart failure, myopathy, breast and other cancers which are believed to be linked to the non-calcemic actions of the parent vitamin D and its daughter steroid hormone.

It is well documented that the darker the skin, the greater the probability of a vitamin D deficiency. Even in southern climates, 55% of African Americans and 22% of Caucasians are deficient. It has been estimated that 40-75% of the world’s population is vitamin D deficient. More than 1 billion people worldwide are affected at a tremendous cost to society.

The link between COVID-19 Risks and Vitamin D

Over the past year, many scientific evidences have been published showing the significant effect that vitamin D status has on COVID-19 disease progression and outcomes. Particularly, higher vitamin D levels can reduce the risk of infection and severity and help prevent death. Whether you are or you are not vaccinated, this knowledge might make a significant difference in this difficult times.

Ghelani et al. [Ref] showed that vitamin D can help protect the lungs from acute injury due to infection from SARS-CoV-2, while vitamin D deficiency contributes to a defective immune response [Ref] and increased disease severity and death. Vitamin D also increases immune cells with antioxidant properties, anti-inflammatory actions, and anti-microbial peptides through its actions within the immune system.

Another Vitamin D and COVID-19 Meta-Analysis was published in December 2021 by Dissanayake et al. [Ref], with similar conclusions. This study comprised A total of 72 studies with data from 1,976,099 individuals. The study found that those with vitamin D deficiency/insufficiency had a

  • 46% higher risk of developing COVID-19
  • 90% higher risk of developing severe COVID-19 disease
  • 107% higher risk of death due to COVID-19

A review by Petrelli et al. [Ref] included 43 studies with data from a total of 612,601 COVID-19 patients that had been published from the beginning of the COVID-19 pandemic through January 31, 2021.This study shows that the

  • Risk of COVID-19 infection was 50% higher among those whose vitamin D levels were below 20 ng/ml (50 nmol/L) compared to those whose levels were at least 20 ng/ml.
  • Risk of severe COVID-19, defined as the need for intensive care and/or mechanical ventilation, was 160% higher among those with vitamin D levels below 20 ng/ml (50 nmol/L) compared to those whose levels were 20 ng/ml or higher
  • Risk of death due to COVID-19 was 22% higher among those with vitamin D levels below 20 ng/ml (50 nmol/L) compared to those whose levels were 20 ng/ml or higher


In summary, it might be a good practice to check your vitamin D level and consider supplementation to correct deficiency. The GrassrootsHealth panel of international vitamin D scientists recommends a vitamin D level between 40-60 ng/ml (100-150 nmol/L). Furthermore, magnesium is an important co-nutrient for vitamin D, and is needed to help vitamin D carry out many of its functions. So include magnesium-rich foods in your diet and/or consider 300-400 mg daily supplementation.

Note: although supplementation of vitamin D and magnesium is generally safe, please consult with your doctor before taking supplements especially if you have any kidney disfunctions.