For those who are not aware of how Vitamin D is important in the body, especially to the immune system, check out Dr Tim Smith on GcMAF, one of the body's immune system stimulants. It causes the macrophages--front line immune system troops--to be more active. Vitamin D is needed for the body to make GcMAF. Viruses and cancer make nagalese that damages the body's ability to make GcMAF. So this is a fight to the death. Either we make enough GcMAF to activate our immune system troops or viruses and cancer will disable our abilityu to make GcMAF. http://gcmaf.timsmithmd.com/
This issue is probably relevant for those who are concerned about the new Chinese virus. Since it will likely take a year for a vaccine to be ready, and who knows how helpful and safe the vaccine will be, people will need other methods for defending oneself from the virus' worst effects.