Of all the things I've read over the past 8 weeks, the Vitamin D association is one of the weakest. There is at least one clinical trial going on using it but there are more trials with Vitamin C. Of course zinc is also popular again.
That's a bit puzzling, Alan. Would you also claim that the evidence for the role that Vitamin D plays in strengthening the immune system, is also weak?
It seems logical to me that any vitamin or mineral that strengthens the immune system will likely reduce the risk of serious consequences resulting from any infection, including Covid-19.
However, I admit that 'correlation' is not the same as 'cause', which has been an issue in Climate Change when proxy records have shown that rises in CO2 levels in the past have often
followed rises in temperature.
There is also the issue that, whilst Vitamin D deficiency might increase the risk of infection from Covid-19, Vitamin D supplements administered
after a person has contracted the virus might not be an effective cure.
Nevertheless, the evidence seems to be strong that the elderly in a population have the greatest deficiency of Vitamin D.
From the 'National Center for Biotechnology Information':
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3356951/"Older adults are at high risk of developing vitamin D insufficiency because of aging. Their skin cannot synthesize vitamin D as efficiently, they are likely to spend more time indoors, and they may have inadequate intakes of the vitamin."Other significant points made in the article:
"The major source of vitamin D for children and adults is exposure to natural sunlight. Thus, the major cause of VDD (Vitamin D Deficiency) is inadequate exposure to sunlight. Wearing a sunscreen with a sun protection factor of 30 reduces vitamin D synthesis in the skin by more than 95%.""Obtaining sufficient vitamin D from natural food sources alone is difficult. Consumption of vitamin D-fortified foods and exposure to some sunlight are essential for maintaining a healthy vitamin D status. Dietary supplements might be required to meet the daily need for vitamin D in some group of people."I believe there are also other benefits in getting one's Vitamin D from sun exposure rather than supplements. These include the production of Nitric Oxide, Serotonin, Endorphin, Brain Derived Meurotropic Factor (BDNF), and Dopamine.
I usually protect myself very well from the sun whenever I go out for a walk, because of the scare about the risk of skin cancer. I protect myself even more when I work in the garden, wearing a long-sleeve shirt, long pants, a hat, and gloves.
However, after reading about the benefits of Vitamin D from sun exposure, I've started taking off my shirt and exposing my upper body to the mid-day sun for about half an hour, on days when the sun shines. We're now approaching winter in Australia. During the next summer I might restrict my exposure to 15 minutes. Too much of anything is bad, by definition.
I'm amazed at the difference in my sense of well-being that has resulted. I usually sleep for 7 hours or more each night and have a snooze in the afternoon. After exposing myself to the mid-day sun on just a few occasions recently, I find I'm sleeping better, need no more than 6 hours sleep, do not need a snooze in the afternoon, have more energy, and generally feel better. I'm 77 by the way.
