Evaluating the connection between diet quality, EpiNutrient intake and epigenetic age: an observational study

Background DNA methylation (DNAm) has unique properties which makes it a potential biomarker for lifestyle-related exposures. Epigenetic clocks, particularly DNAm-based biological age predictors [epigenetic age (EA)], represent an exciting new area of clinical research and deviations of EA from chronological age [epigenetic age acceleration (EAA)] have been linked to overall health, age-related diseases, and environmental exposures. Objectives This observational study investigates the relationships between biological aging and various dietary factors within the LifeLines-DEEP Cohort. These factors include diet quality, processed food consumption, dietary glycemic load, and intake of vitamins involved in maintaining the epigenetic homeostasis (vitamins B-9, B-12, B-6, B-2, and C). Methods Dietary records collected using food-frequency questionnaires were used to estimate diet quality [LifeLines Diet Score (LLDS)], measure the intake of unprocessed/ultraprocessed food according to the NOVA food classification system, and the adequacy of the dietary intake of vitamins B-9, B-12, B-2, B-6, and C. EA using Horvath, Hannum, Levine, and Horvath2 epigenetic clock models and DNAm-predicted telomere length (DNAm-TL) were calculated from DNAm data in 760 subjects. Associations between dietary factors and EAA were tested, adjusting for sex, energy intake, and body composition. Results LLDS was associated with EAA (EAA_Horvath: β: −0.148; P = 1 × 10−4; EAA_Hannum: β: −0.148; P = 9 × 10−5; EAA_Levine: β: −0.174; P = 1 × 10−5; and EAA_Horvath2: β: −0.176; P = 4 × 10−6) and DNAm-TL (β: 0.116; P = 0.003). Particularly, EAA was associated with dietary glycemic load (EAA_Horvath: β: 0.476; P = 9 × 10−10; EAA_Hannum: β: 0.565; P = 1 × 10−13; EAA_Levine: β: 0.469; P = 5 × 10−9; EAA_Horvath2: β: 0.569; P = 1 × 10−13; and DNAmTL adjusted for age: β: −0.340; P = 2 × 10−5) and different measures of food processing (NOVA classes 1 and 4). Positive EAA was also associated with inadequate intake of vitamin B-12 (EAA_Horvath: β: −0.167; P = 0.002; EAA_Hannum: β: −0.144; P = 0.007; and EAA_Horvath2: β: −0.126; P = 0.019) and C (EAA_Hannum: β: −0.136; P = 0.010 and EAA_Horvath2: β: −0.151; P = 0.005). Conclusions Our findings corroborate the hypothesis that nutrition plays a pivotal role in influencing epigenetic homeostasis, especially DNAm, thereby contributing to individual health trajectories and the pace of aging.