Even though the mainstream is focused on vaccination and pharmaceutical solutions to COVID-19, there is increasing evidence showing that vitamin D is vitally important both in the prevention of severe disease and in treatment in the hospital setting as it modulates the immune system. A new piece of research from Spain followed the treatment of 76 patients who were hospitalised with COVID-19. They were given the same standard of care, except 50 patients were also given calcifediol, a form of vitamin D3. In this group, only one patient (2%) was admitted to the ICU and recovered, whereas of the 26 untreated, 13 (50%) needed transfer to the ICU where 2 died and 11 recovered. This result is statistically significant and hopefully will be replicated in future larger trials.
The following graph shows the severity of COVID-19 symptoms by vitamin D status, indicating that it is important for prevention as well as treatment.
Vitamin D is actually misnamed as technically it is a hormone not a vitamin. It is synthesised in the skin in response to ultraviolet light from the sun, and is then transported to the liver and kidneys where it is converted to an active hormone. There are receptors throughout the tissues of the body, where its functions include:
- Modulating the function of the immune system, stimulating it to produce antibodies
- Regulating and suppressing the cytokine inflammatory response. The ability to downregulate the inflammatory response is particularly important for COVID-19, as out of control inflammation (cytokine storm) is a primary cause of death
- Essential for the proper absorption of calcium into bones therefore reducing fracture risk and improving bone health
- Important for proper contraction and relaxation of muscles, so making us stronger
- There are many vitamin D receptors in the lungs and so can reduce inflammation here, which is very important in all respiratory illnesses
- Reducing the risk of high blood pressure and cardiovascular disease
- Helping to regulate kidney function
- Protective of cognitive function. Research has shown that seniors with low vitamin D levels have an increased risk of dementia
- Reducing the risk of depression and multiple sclerosis
- There is even some research that says that it is necessary for leptin, the satiety hormone, to work well. So low levels could leave you permanently hungry, making it much harder to lose weight.
As you can see, there are many reasons beyond COVID-19 to ensure that your vitamin D levels are optimal. A final thought is that if you do decide that you need supplementation beyond extra sunlight, which is going to be hard to get in the UK as we head into the winter months, you should seriously consider adding vitamin K2 into the mix. D and K2 work together to ensure that calcium is deposited into bones rather than into the soft tissues and arteries, thus improving bone density rather than increasing atherosclerosis. Vitamin K2 can be obtained naturally in natto (a Japanese fermented bean product that many people find disgusting, although we quite like it), some hard cheeses, and liver, but most people are not eating enough of these to get sufficient amounts of this vitamin, making supplementation even more important. So get tested, get some sun and, if your levels aren’t up to snuff, then get some supplements.