Association Between Ultra-Processed Food Consumption and Leucocyte Telomere Length: A cross-sectional study of UK Biobank

This study investigates the association between consumption of ultra-processed foods and leucocyte telomere length. This cross-sectional study utilized data from the UK Biobank, including a total of 64,690 participants. LTL was measured using Q-PCR with natural logarithmic conversion and Z-score normalization. Dietary data were collected through a 24-hour recall questionnaire from 2009 to 2010. UPFs were identified using the Nova food classification as either a continuous or a categorical variable respectively. Multiple linear regression models were employed to analyze the association between UPF consumption and LTL. The included participants had an average age of 56.26 years, of whom 55.2% were female. After adjusting for demographic and health-related variables, LTL exhibited a decrease of 0.005 (95% CI:−0.007,−0.002) with one UPF serving increase. Compared to participants consuming ≤3.5 servings/day, those consuming 3.5 to <6 servings showed a shortening of LTL by 0.025 (95% CI: −0.046, −0.003). Participants consuming 6 to ≤8 servings/day and >8 servings/day had LTL shortening of 0.032 (95% CI: −0.054, −0.011) and 0.037 (95% CI: −0.060, −0.014), respectively (P for trend=0.002). Subgroup analyses by UPF subclasses revealed that the consumption of ready-to-eat/heated food (β=−0.010, 95% CI:−0.016,−0.004), beans and potatoes (β=−0.027, 95% CI:−0.043,−0.012), animal-based products (β=−0.012, 95% CI:−0.020,−0.005), artificial sugar (β=−0.014, 95% CI:−0.025,−0.003), and beverages (β=−0.005, 95% CI:−0.009,−0.001) showed negative associations with LTL. Conversely, breakfast cereals (β=0.022, 95% CI:0.006,0.038) and vegetarian alternatives (β=0.056, 95% CI:0.026,0.085) showed positive correlations with LTL. Our study found that a higher consumption of total UPF was associated with a shorter LTL. However, some UPFs may be associated with longer LTL, depending on their nutritional composition.