Dietary patterns and practices and leucocyte telomere length: Findings from the UK Biobank

Background

Shorter telomere length (TL) is associated with risk of several age-related diseases and decreased lifespan, but the extent to which dietary patterns and practices associate with TL is uncertain.

Objective

This study aimed to investigate the association of dietary patterns and practices and leucocyte TL (LTL).

Design

This was a cross-sectional study.

Participants

/ setting: Data collected voluntarily from up to 422,797 UK Biobank participants, during 2006-2010.

Main outcome measures

LTL was measured as a ratio of the telomere repeat number to a single–copy gene and was loge-transformed and standardised (z-LTL).

Statistical analysis

A-priori adherence to the Mediterranean diet was assessed through the MedDietScore. Principal component analysis was used to a-posteriori extract the “Meat” and “Prudent” dietary patterns. Additional dietary practices considered were the self-reported adherence to “Vegetarian” diet, “Eating 5-a-day of fruit and vegetables” and “Abstaining from eggs/dairy/wheat/sugar”. Associations between quintiles of dietary patterns or adherence to dietary practices with z-LTL were investigated through multivariable linear regression models (adjusted for demographic, lifestyle and clinical characteristics).

Results

Adherence to the “Mediterranean” and the “Prudent” patterns, was positively associated with LTL, with an effect magnitude in z-LTL of 0.020SD and 0.014SD, respectively, for the highest vs the lowest quintile of adherence to the pattern (both P<0.05). Conversely, a reversed association between quintile of the “Meat” pattern and LTL was observed, with z-LTL being on average shorter by 0.025SD (P=6.12x10-05) for participants in the highest quintile of the pattern compared to the lowest quintile. For adherents to “5-a-day” z-LTL was on average longer by 0.027SD (P=5.36x10-09), and for “abstainers”, LTL was shorter by 0.016SD (P=2.51x10-04). The association of LTL with a vegetarian diet was non-significant after adjustment for demographic, lifestyle and clinical characteristics.

Conclusion

Several dietary patterns and practices, associated with beneficial health effects, are significantly associated with longer LTL. However, the magnitude of the association was small, and any clinical relevance is uncertain.