Biological age and diet: Measuring the impact of lifestyle on a 6CpG-epigenetic clock

BACKGROUND: Changes in DNA methylation along the life have been documented, and environmental exposures (including diet, physical activity and smoking) can accelerate or decelerate this process. The epigenetic clock estimates the biological age of an individual measuring methylation patterns in specific areas of its genome. Recently, a new epigenetic clock based on 6 CpGs has been proposed, with high potential to become an easy accessible tool able to measure the epigenetic age (EA) of an individual. OBJECTIVES: This study aims to validate the 6 CpG epigenetic clock comparing it with other biomarkers of aging such as telomere length (TL) and methylation in the long interspersed nuclear elements (LINE-1). The impact of life-style associated factors on these molecular marks has been evaluated. METHODS: 200 healthy participants having extreme dietary patterns (healthy vs western diet) were selected. Dietary intakes, body composition, physical activity level and smoking has been assessed. DNA extracted from whole blood was used to measure the 6CpG-EA, TL and LINE-1 methylation levels. RESULTS: 6CpG-EA was positively correlated with chronological age (r = 0.591; p = 7.2*10 - 20) and negatively with TL (r = –0.150; p = 0.040) and LINE-1 methylation (r = –0.240; p = 0.001). Despite no significant associations were detected with the overall diet quality (HEI), 6CpG-EA was correlated with dietary intakes of nutrients involved in the one-carbon (1 C) metabolism, especially in the western diet group. CONCLUSION: These results support the 6CpG epigenetic clock as an easy accessible tool to estimate biological age, in accordance with other molecular markers of aging, and suggest that EA can be modulated by micronutrients involved in the 1 C metabolism.