Mediterranean diet and telomere length in Nurses’ Health Study: population based cohort study

OBJECTIVE To examine whether adherence to the Mediterranean diet was associated with longer telomere length, a biomarker of aging. DESIGN Population based cohort study. SETTING Nurses' Health Study, an ongoing prospective cohort study of 121,700 nurses enrolled in 1976; in 1989-90 a subset of 32,825 women provided blood samples. PARTICIPANTS 4676 disease-free women from nested case-control studies within the Nurses' Health Study with telomere length measured who also completed food frequency questionnaires. MAIN OUTCOME MEASURE Association between relative telomere lengths in peripheral blood leukocytes measured by quantitative real time polymerase chain reaction and Alternate Mediterranean Diet score calculated from self reported dietary data. RESULTS Greater adherence to the Mediterranean diet was associated with longer telomeres after adjustment for potential confounders. Least squares mean telomere length z scores were -0.038 (SE 0.035) for the lowest Mediterranean diet score groups and 0.072 (0.030) for the highest group (P for trend = 0.004). CONCLUSION In this large study, greater adherence to the Mediterranean diet was associated with longer telomeres. These results further support the benefits of adherence to the Mediterranean diet for promoting health and longevity.