Vitamin D

Roc Ordman takes 2,000-5,000 IU of vitamin D3 daily. At Linus Pauling conferences, Dr. Michael Holick, Boston University endocrinologist, has increased his recommendation progressively to 2,000, stating experts now take 5,000. “Recent evidence suggests that vitamin D intakes above current recommendations may be associated with better health outcomes. However, optimal serum concentrations of 25-hydroxyvitamin D [25(OH)D] have not been defined. This review summarizes evidence from studies that evaluated thresholds for serum 25(OH)D concentrations in relation to bone mineral density (BMD), lower-extremity function, dental health, and risk of falls, fractures, and colorectal cancer. For all endpoints, the most advantageous serum concentrations of 25(OH)D begin at 75 nmol/L (30 ng/mL), and the best are between 90 and 100 nmol/L (36–40 ng/mL). In most persons, these concentrations could not be reached with the currently recommended intakes of 200 and 600 IU vitamin D/d for younger and older adults, respectively.”

BASIS OF IMMUNITY: For many years, it was believed that humans only had cellular immunity, based on B- and T- cells. The B cells produced antibodies in response to antigens, in a process that was orchestrated by T-cells and took a week or two. To get a strong immune response required 2 exposures to the antigen, the first to activate T- and B-cells initially, the second to get them to divide rapidly and produce memory T-cells which give lasting immunity.

THEN innate immunity was discovered, based on vitamin D (article). Vitamin D is converted into vitamin D metabolites which react directly and immediately with the first antigens found from foreign substances in the body. So the first cold or COVID virus that enters the blood may be destroyed by the vitamin D metabolite and you never become ill. Many of us rarely get sick because we take plenty of vitamin D. Doctors now check our vitamin D levels for a routine physical. But they only look for a much lower level around 10ng/ml, when for immune protection one should have 25ng/ml as shown in the graph below.
BASIS FOR MUSCLE REJUVENATION: Vitamin D increases Klotho protein levels to promote muscles to regrow and slow aging, particularly with 65+ years old. https://www.sciencedaily.com/releases/2021/04/210420121430.htm;

HOWEVER, this graph suggests that too much or too little vitamin D may be hazardous.

Finally, for treatment of COVID by doctors, here is the recommendation.