Immunity is important in helping the body fight off pathogens or foreign substances effectively. Having a sufficient level of immune-boosting or immune-enhancing vitamins, along with proper health care and infection prevention, is considered a good way to prevent diseases.
Since the outbreak of COVID-19, there have been many research studies on vitamin D based on large study groups. For example, 82.2% of the group infected with COVID-19 were vitamin D deficient (<20 ng/ml), those with low vitamin D (<30 ng/ml) who contracted COVID-19 were 6 times more likely to require ventilators than those with normal vitamin D levels and had a 15 times higher chance of death. High-risk populations with NCDs (diabetes, hypertension, cardiovascular and cerebrovascular diseases, respiratory diseases, and various cancers) all have the problem of low vitamin D levels, among others.
Benefits of Vitamin D in terms of COVID-19
Vitamin D is a free vitamin obtained from sunlight, but unfortunately, most Thai people have vitamin D levels below the standard. So how does vitamin D help prevent and reduce the severity if infected with COVID-19? Let’s find out…
Normally, all types of white blood cells have vitamin D receptors on their cell membranes. When the virus enters our respiratory system, the phage 1 innate immunity response occurs. Phagocytic white blood cells such as macrophages, neutrophils, and the powerful NK cells directly confront the virus. Infected lung cells secrete interferon to signal neighboring cells to prepare for the virus and recruit more white blood cells. At this point, vitamin D enters the white blood cells to stimulate the secretion of beta-defensins and cathelicidins, which help destroy the virus by piercing its envelope and breaking down viral proteins into parts until the virus is neutralized. If the body has sufficient vitamin D levels, the infected person may have almost no symptoms at all.
Meanwhile, dendritic cells collect viral debris to present to T cells to join the fight, triggering phage 2 adaptive immunity T cells. If the lungs are full of infected cells, T cells multiply into cytotoxic T cells (Th1) that produce perforin, which can punch holes in infected cells and release granzyme inside, causing those infected cells to die to prevent the virus replicating inside the cells from spreading. White blood cells communicate with each other using substances called cytokines. In prolonged battles with infected lung cells, a condition called a cytokine storm can occur, causing symptoms ranging from mild cough, difficulty breathing, loss of smell, to severe conditions such as acute kidney failure in some cases. However, these severe processes can also be inhibited by vitamin D.
Vitamin D activates adaptive immunity phage 2 T cells differently by promoting T cells to multiply into T helper cells (Th2) and suppressing cytotoxic T cells (Th1), which mainly destroy infected lung cells. T helper cells (Th2) stimulate B cells to become plasma cells that produce antibodies to bind the virus, preventing the virus from entering lung cells. The virus is then captured and destroyed by macrophages, neutrophils, and NK cells (phage 1) without excessively damaging lung cells.
Therefore, we should get some sunlight. It is recommended that the best time to get sunlight is between 10 a.m. and 2 p.m. for an average of 5-10 minutes. However, if you have dark skin, you may need to be in the sun longer, about 30-40 minutes. If you really cannot get sunlight, you can supplement vitamin D, but the appropriate dosage should depend on blood vitamin D level test results for the best outcome.
Anti-Aging and Health Rehabilitation Physician
Obstetrician-Gynecologist and Sexual Medicine Physician
Phyathai 3 Hospital
