Vitamin D from the sun increases stem cells. Deficiency causes stem cell issues. We maintain blood stem cells for the immune system, increasing new immune cells and preventing stem cell exhaustion in the brain, immune system, and muscles. This supports longevity. #VitaminD #StemCells #ImmunityBoost #Longevity #SunlightBenefits #HealthTips #Wellness #HealthyLiving #ImmuneSystem #BrainHealth