Researchers found that vitamin D supplements helped preserve telomere length—a marker of aging—but experts say lifestyle and context matter more.
https://www.theepochtimes.com/health/vitamin-d-may-help-slow-cellular-aging-study-finds-but-experts-urge-caution-5865633(I don't think above is an advertorial, as it doesnt link directly to any product from what I can tell)
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A second interesting historical link
https://www.cnbc.com/2020/09/14/supplements-white-house-advisor-fauci-takes-every-day-to-help-keep-his-immune-system-healthy.htmlAccording to Dr. Anthony Fauci, most “so-called immune boosting supplements” actually do “nothing.” However, there are two vitamins Fauci does recommend to help keep your immune system healthy.
“If you are deficient in vitamin D, that does have an impact on your susceptibility to infection. So I would not mind recommending, and I do it myself taking vitamin D supplements,” Fauci, 79, said during an Instagram Live on Thursday, when actress Jennifer Garner asked Fauci about immune-boosting supplements.
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Also from AI
There is no verified public record confirming how much Vitamin D Dr. Anthony Fauci takes, however, during a 2020 interview, he mentioned taking vitamin D supplements (reportedly around 6,000 IU) to support immune health, though he did not specify an exact daily dosage.