Overview

• The study was randomized, double-blind and placebo-controlled, enrolling men over 50 and women over 55 across the U.S.
• Participants taking 2,000 IU of vitamin D3 daily showed significantly less telomere shortening compared with placebo, equivalent to almost three years slower biological aging.
• Omega-3 supplements had no significant effect on telomere length over the four-year follow-up period.
• Earlier phases of the VITAL trial linked vitamin D supplementation to reduced inflammation and lower risks of advanced cancers and autoimmune diseases.
• General guidelines recommend 10 micrograms of vitamin D daily for bone health; researchers propose that higher-dose supplementation may benefit individuals with elevated inflammation or age-related disease risk.