4-years of supplementation with 2000 IU/day vitamin D3 reduced telomere attrition by 140 bp, suggesting that vit D3 daily supplementation with or without n-3 FAs might have a role in counteracting telomere erosion or cell senescence https://ajcn.nutrition.org/article/S0002-9165(25)00255-2/abstract Vitamin D3 and marine ω-3 fatty acids supplementation and leukocyte telomere length: 4-year findings from the VITamin D and OmegA-3 TriaL (VITAL) randomized controlled trial https://www.youtube.com/watch?v=DZrolyDps9o