Vitamin D is heavily used to both prevent or curtail the progression of Covid-19. However, it’s noteworthy that current evidence is too limited to recommend for or against vitamin D supplementation among patients with Covid-19. Excessive use of vitamin D may predispose you to high blood and kidney calcium levels.
Vitamin D, a fat-soluble vitamin, is rarely abundant in food except for fatty fish livers. Under the direct action of ultraviolet light from sun exposure, the skin manufactures it from cholesterol. The immediate product undergoes further changes from the liver and kidney to an active form (1, 25-dihydroxyvitamin D) that the body uses to normally function.
Bones, the structures that confer support to our bodies, are active metabolic organs. They regulate calcium and phosphate metabolism, as well as magnesium storage with vitamin D taking centre stage. Calcium is an integral part of cellular function. Vitamin D functions by anchoring onto vitamin D receptors and regulates gene transcription.
Almost all cells carry these receptors, including immune cells like B cells, T cells, and antigen-presenting cells (APC). Much as the kidney is the sole source of the active form of the vitamin, immune cells can synthesize the active form of the vitamin. It can therefore modify body immunity.
Melanocytes, the cells that synthesize melanin (the pigment that darkens your skin), interfere with vitamin D synthesis in the skin, especially if you do not get enough sun exposure. Older people tend to have low blood levels of vitamin D, as do people with obesity and hypertension. Obesity and hypertension may increase the risk of unfavourable outcomes among patients with Covid-19. Low levels of the vitamin may increase the propensity to suffer from pneumonia.
Vitamin D supplements may increase the number of immune cells in the body and their activity. These immune cells protect the body against infections, specifically acute respiratory tract infection. The supplements neither shorten hospital admission length nor reduce mortality among critically ill patients deficient in the vitamin. Moreover, increased levels may predispose patients to hypercalcaemia and nephrocalcinosis.
Currently available data from clinical trials deduce that supplementation does not reduce the length of hospital stay nor mortality among patients with severe Covid-19. However, the data is too limited to draw any definite conclusive remarks. More trials are ongoing to delineate its importance in ameliorating the symptoms of Covid-19 or even prevent it.
Increased utilisation of this vitamin among patients with Covid-19 resides on the notion that the vitamin has immunomodulatory effects that can protect one from acute respiratory tract infection. It noteworthy, however, that high vitamin consumption is harmful to your body. Take it with caution. You can get enough of it from adequate exposure to the sun in addition to maintaining a healthy body. You can as well stop overdosing yourself with vitamin supplements and feed yourself well. There’s no substitute for good feeding and proper exercising, as well as exquisite sanitation.