"Can Vitamin D Slow Aging? A New Study Says Yes – But There's a Catch :" ScienceAlert

https://www.sciencealert.com/can-vitamin-d-slow-aging-a-new-study-says-yes-but-theres-a-catch 

"There's also no agreement on the right dose. The Augusta researchers used 2,000 IU daily – much higher than the current recommended intake of 600 IU for under-70s and 800 IU for older adults. Yet other research suggests just 400 IU might help prevent colds...''

"Aging Spreads Through The Body Like An Infection, And This Protein Could Be To Blame"

https://studyfinds.org/aging-contagious-protein/ 

"When researchers blocked these pathways with existing drugs, the aging effects were eliminated, confirming that the reduced form acts through these mechanisms. According to the study, "Extracellular ReHMGB1, but not its oxidized form, robustly induced senescence-like phenotypes across multiple cell types and tissues..."