The association of serum levels of vitamin D with leucocyte telomere length, as a marker of biological aging: A meta-analysis.
Level 3 - non-randomized controlled study
Systematic review and meta-analysis of observational studies
PubMed 41650046 · doi:10.1097/MD.0000000000044487
What was done
Authors conducted a systematic review and meta-analysis of 21 studies totaling 185,191 participants identified through PubMed, Scopus, Google Scholar, ClinicalTrials.gov, and Cochrane Library searches through February 2025. The analysis evaluated the association between circulating 25-hydroxyvitamin D (25(OH)D) concentrations and leukocyte telomere length (LTL) using random-effects models, reporting standardized beta (β) coefficients with 95% confidence intervals.
What was found
Serum 25(OH)D levels were weakly positively associated with LTL overall (β = 0.04, 95% CI = 0.02-0.06), with substantial heterogeneity across studies (I² = 89.1%, P ≤ 0.001). Subgroup analyses showed significant positive associations in: - Adults (β = 0.04, 95% CI = 0.03-0.06) - Women (β = 0.05, 95% CI = 0.01-0.08) - Individuals with vitamin D deficiency (β = 0.22, 95% CI = 0.01-0.43) - Studies that adjusted for covariates (β = 0.05, 95% CI = 0.01-0.08) No significant associations were found in men, children, individuals with serum 25(OH)D ≥ 30 ng/mL, or studies without covariate adjustments. Relationships were not influenced by the method of telomere assessment, body mass index, smoking status, or sample size.
Why it matters
This review synthesizes population-level data linking higher vitamin D status to longer leukocyte telomeres, highlighting that any potential association is largely concentrated in deficient states and specific demographic subgroups.
Limits
The underlying studies are observational, precluding causal inference. Between-study heterogeneity was very high (I² = 89.1%). The overall effect size is very modest (β = 0.04), and the abstract does not report individual study designs (cross-sectional versus longitudinal), potential residual confounders, or interventional validation.
Cited by
- contradicts Circulating vitamin D levels between 40 and 60 ng/mL are associated with longer telomeres.