Dr Ashu Rastogi is a Asso Professor, Dept of Endocrinology at PGI Chandigarh

Many studies have now found high association between Vitamin D levels and COVID-19 severity and mortality. Such studies showed that patients with COVID-19 had significantly lower Vitamin D levels. In addition, fever was significantly higher in patients who had deficient Vitamin D levels compared with patients who had sufficient levels. Additionally, it has been found that older adults with Vitamin D deficiency and COVID-19 had worse morbidity outcomes compared with those who were not deficient.

Vitamin D is a fat-soluble vitamin that plays a number of critical roles in body. This nutrient is especially important for immune system health. Since, it is a group of fat-soluble compounds responsible for intestinal absorption of calcium, magnesium, and phosphate, and for a variety of additional biological effects; low levels of Vitamin D can increase the likelihood of developing multiple acute and chronic ailments. A weaker immune system means body’s weak defence against infection and disease.

A prospective, interventional study found that a high dose of calcifediol reduced the need for intensive care stays in patients infected with COVID-19. Because Vitamin D deficiency has been shown to potentially increase the risk of severe respiratory infections, Vitamin D supplements are suggested for prevention and treatment of COVID-19 complications, especially acute respiratory disease. Nowadays many brands of Vitamin D supplementation are available in market like D3 Must, Caldikind, Calshine, etc.

It is noticed that those receiving Vitamin D supplementation have fewer respiratory tract infections.

According to the SHADE study published by BMJ and led by Dr Rastogi and his team, greater proportion of vitamin D-deficient individuals with SARS-CoV-2 infection turned SARS-CoV-2 RNA negative with a significant decrease in fibrinogen on high-dose cholecalciferol supplementation.

We have seen that seven days high dose of Vitamin D3 (60000 IU) supplementation helps in Coronavirus clearance.

Given the evidence supporting the role of vitamin D in modulating immune function, and the impact of vitamin D supplementation on vitamin D-deficient patients with COVID-19, practical recommendations should be synthesised as follows:

• Current public health guidelines for optimising vitamin D status should be followed always
• Patients hospitalised with COVID-19 should have baseline serum 25(OH)D concentrations measured and should be supplemented to a level >30ng/mL (optimal 40-60ng/mL), especially when the baseline level is <10ng/mL
• In COVID-19 patients with 25(OH)D serum concentrations under 20ng/mL the recommended dose for correction of deficiency is 6000-7000 oral IU/ day for 6-8 weeks. For maintenance, the dose varies from 2000 to 3000 oral IU/day depending on the age and clinical condition of the individual up to reach optimal concentrations.
• When it is not possible to measure baseline 25(OH)D concentrations in COVID-19 patients, it seems essential supplementing with 2000-3000 oral IU per day up to the suggested optimal serum concentrations (40-60ng/mL).

Though India is a subtropical country with adequate sunlight, Vitamin D deficiency is prevalent. Sunlight rapidly inactivate SARS-CoV-2 on surfaces, suggesting that there may be an environmental benefit associated with Vitamin D as a result of sun exposure. It is necessary for people to understand the importance of Vitamin D so that they can take relevant medications.