Although there is currently no cure for Covid-19, research is being conducted to investigate the extent to which positive levels of vitamin D – also known as the ‘sunshine vitamin’ – can help to maintain a healthy immune system that may provide some protection against respiratory illnesses, including Covid-19. 

Vitamin D – included in diary products such as milk and yoghurt – has long been recognised as necessary for the optimum functioning of the immune system. For its part, the body’s immune system is the first line of defence against infection and disease. 

Vitamin D, a fat-soluble vitamin than enhances the intestinal absorption of calcium and phosphorus, has both an anti-inflammatory and immune-regulatory property and is necessary for the activation of immune system defences. As such it plays an important role in promoting immune response. Healthy levels of vitamin D enhances the function of immune cells that provide protection against pathogens. 

Low levels of vitamin D have been associated with increased susceptibility to infection, disease, and immune-related disorders, including an increased risk of respiratory diseases such as tuberculosis, asthma, chronic obstructive pulmonary disease and viral and bacterial respiratory infections. 

Deficiencies in vitamin D, on the other hand, may compromise immune response and increase the risk of infection and disease. Vitamin D deficiencies have been linked to decreased lung function which may affect how well the body is able to fight respiratory infections. 

Researchers hypothesise that a vitamin D deficiency may increase the risk of severe Covid-19 complications. As a result, a number of trials around the world are investigating the effects of vitamin D supplementation in people with Covid-19 with one study revealing that patients hospitalised with Covid-19 who had sufficient levels of vitamin D had a decreased risk for adverse outcomes and death. 

Earlier this year researchers at the Queen Mary University of London launched a six-month study involving 5 000 people to investigate whether high doses of vitamin can potentially reduce winter respiratory infections, including Covid-19. Health experts are suggesting that healthy levels of vitamin D may assist Covid-19 patients to avoid a cytokine storm. The latter involves the immune system over-reacting and attacking the body’s own cells and tissues. 

While these studies have yet to be concluded, there is certainly no harm in increasing your intake of dairy products such as milk and yoghurt, the latter which should be unflavoured and sugar-free versions which include live and active cultures to boost your immune system. 

Dairy foods play a key role in a balance diet given that they are a cost-effective and convenient way to access more than 10 essential nutrients, including calcium, vitamins A, B and D, riboflavin, carbohydrates, protein, potassium, phosphorous, magnesium and zinc. 

Vitamin D has the added benefit of ensuring healthy bones and blood cells. In addition it aids the absorption of minerals such as calcium and phosphorous. 

As South Africa continues to battle the third wave of Covid-19 infections, maintaining a healthy immune system is imperative.