Association between diet consumption and altered telomere length in leukocytes

Leukocyte telomere length (LTL) measures the protective caps (telomeres) on the ends of white blood cell chromosomes, acting as a biomarker for biological aging; shorter LTL often signals faster aging and higher risk for age-related diseases Observational studies suggest dietary factors influence leukocyte telomere length, yet causality remains unproven. Using Mendelian randomization (MR) and colocalisation analyses, researchers investigated causal relationships between 38 dietary phenotypes and leukocyte telomere length to clarify conflicting evidence on Mediterranean diet components (alcohol, nuts) and biological aging.
This MR study provides genetic evidence that moderate alcohol consumption, including wine, accelerates telomere shortening, which contradicts previous observational claims regarding the benefits of the Mediterranean diet that often emphasise wine as a protective component. In contrast, nut intake aligns with dietary recommendations for anti-aging. These findings challenge the prevailing notion of the Mediterranean diet as a uniformly beneficial model for longevity by revealing heterogeneity and even antagonistic effects among its components (alcohol vs nuts) on aging.
The study lends evidence to the need to reassess the role of alcohol in longevity-promoting diets. Public health strategies should advocate reducing alcohol consumption and increasing nut intake to mitigate the risk of age-related diseases, the study authors say.
Source: Wang B, He J, Pei Z, Tao C, Song E. Mendelian randomization and colocalization analyses reveal an association between diet consumption and altered telomere length in leukocytes. Medicine (Baltimore). 2025 Nov 21;104(47):e45825.