01/03/2026
I have Vit D3 available from Nutrition-West in two sizes;
5000iu and 2500iu with probiotics
A large randomized controlled trial supported by the National Heart, Lung, and Blood Institute (NHLBI) examined whether vitamin D affects cellular aging by measuring telomere length in white blood cells. The analysis was part of the VITAL trial, which followed nearly 26,000 adults over five years. More than 900 participants were included in the telomere sub-study, with half taking 2,000 IU of vitamin D3 daily and the other half taking a placebo.
After four years, participants taking vitamin D showed significantly less telomere shortening, losing about 140 fewer DNA base pairs compared with placebo. Since telomeres shorten as cells divide and age, researchers estimate this difference could equal up to three years less biological aging. The findings were published in The American Journal of Clinical Nutrition and suggest vitamin D may help preserve genetic stability as we age, though researchers note replication is still needed.