Healthy eating patterns and epigenetic measures of biological age

Abstract

Background: Healthy eating is associated with lower risks of disease and mortality, but the mechanisms underlying these associations are unclear. Age is strongly related to health outcomes, and biological age can be estimated using the blood methylome.

Objectives: To determine whether healthy eating patterns are associated with methylation-based measures of biological age.

Methods: Among women in the Sister Study, we calculated scores on 4 recommendation-based healthy eating indexes [Dietary Approaches to Stop Hypertension diet, Healthy Eating Index-2015, Alternative Healthy Eating Index (aHEI-2010), and the Alternative Mediterranean diet] using a validated 110-item Block FFQ completed at enrollment. Genome-wide DNA methylation data were generated using the HumanMethylation450 BeadChip on whole blood samples collected at enrollment from a case-cohort sample of 2694 women and were used to calculate 4 measures of epigenetic age acceleration (Hannum AgeAccel, Horvath AgeAccel, PhenoAgeAccel, and GrimAgeAccel). Linear regression models, adjusted for covariates and cohort sampling weights, were used to examine cross-sectional associations between eating patterns and measures of biological age.

Results: All 4 healthy eating indexes had inverse associations with epigenetic age acceleration, most notably with PhenoAgeAccel and GrimAgeAccel. Of these, the strongest associations were for aHEI-2010 [per 1-SD increase in diet quality, PhenoAgeAccel β = -0.5 y (95% CI: -0.8 to -0.2 y) and GrimAgeAccel β = -0.4 y (95% CI: -0.6 to -0.3 y)]. Although effect modification was not observed for most lifestyle factors, in analyses stratified by physical activity, the benefits of a healthy diet on epigenetic age acceleration were more pronounced among women who did not meet physical activity guidelines (reporting <2.5 h/wk of exercise).

Conclusions: Higher diet quality is inversely associated with methylation-based measures of biological age. Improving diet could have the most benefits in lowering biological age among women with lower levels of physical activity. This trial was registered at clinicaltrials.gov as NCT00047970.

Keywords: DNA methylation; biological age; diet quality; epigenetic clocks; healthy eating.

Published by Oxford University Press on behalf of the American Society for Nutrition 2021.

Figures

FIGURE 1

Flow chart for the study population. Description of the inclusion criteria for the subset of Sister Study participants included in this study.

FIGURE 2

Associations between recommendation-based diets and the 4 measures of epigenetic age acceleration. Plots display the β-coefficients and 95% CIs from adjusted linear regression models, which represent the adjusted mean difference for the 4 individual AgeAccel metrics per 1-SD increase in diet quality, for the (A) DASH diet, (B) Healthy Eating Index–2015, (C) Alternative Health Eating Index–2010, and (D) Alternative Mediterranean diet (n = 2694). Abbreviation: DASH, Dietary Approaches to Stop Hypertension.

FIGURE 3

Associations between recommendation-based diets and the 4 measures of epigenetic age acceleration, stratified by physical activity level. Plots display the β-coefficients and 95% CIs from adjusted linear regression models, which represent the adjusted mean difference for the 4 individual AgeAccel metrics per 1-SD increase in diet quality, for the (A) DASH diet, (B) Healthy Eating Index–2015, (C) Alternative Health Eating Index–2010, and (D) Alternative Mediterranean diet among women who did not meet physical activity guidelines (n = 1541) and for women who did (≥2.5 h/wk, gray lines; n = 1153). Significant statistical interactions determined by cross-product terms were observed for physical activity on the relationships between PhenoAgeAccel and the DASH diet (P-interaction = 0.04) and the aMed diet (P-interaction = 0.04). Abbreviation: DASH, Dietary Approaches to Stop Hypertension.