Several dietary patterns are suggested to benefit health, potentially through DNA methylation changes. However, to what extent adherence to so-called healthy diets overlaps, whether these dietary patterns are equally beneficial, and whether they affect health outcomes through the same molecular mechanisms, remains unclear. Therefore, we investigated the overlap in adherence to ten diet quality scores, and examined the associations of these scores with both biological aging markers and DNA methylation profiles. We used data from the Rhineland Study, a large population-based cohort, and validated our findings using corresponding data from the independent EPIC-Potsdam cohort. Interestingly, we found minimal overlap of participants in the top 25% of adherence across different diet quality scores. Adherence to a healthy dietary pattern was associated with reduced epigenetic age acceleration regardless of the specific dietary pattern, except for the EAT-Lancet diet. Different dietary patterns were associated with distinct methylation profiles, which however largely converged onto the same biological pathways. Our research thus indicates that general adherence to a healthy dietary pattern promotes health through similar epigenetic mechanisms, despite variations in dietary composition.

The authors have declared no competing interest.

The Rhineland Study is funded by the German Center for Neurodegenerative Diseases (DZNE). This work was supported through the Federal Ministry of Education and Research under the Diet Body Brain Competence Cluster in Nutrition Research (grant numbers 01EA1410C and 01EA1809C) and in the framework PreBeDem - Mit Pravention und Behandlung gegen Demenz (grant number 01KX2230), the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's Excellence Strategy (EXC 2151 390873048) and through SFB1454, project number 432325352, and the Helmholtz Association under the 2023 and 2024 Innovation Pool. DL is partly supported by a grant from the Alzheimer's Association (24AARFD-1192360). NAA is partly supported by a European Research Council Starting Grant (Number: 101041677). The work in EPIC-Potsdam was supported by a grant from the German Federal Ministry of Education and Research and the State of Brandenburg to the German Center for Diabetes Research (DZD; 82DZD00302 and 82DZD03D03).

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The data used in this manuscript is not publicly available due to data protection regulations. Access to the Rhineland Study data can be provided to scientists in accordance with the study's Data Use and Access Policy. Requests for additional information and/or access to the datasets can be sent to RS-DUACdzne.de. Information on data access and contact details for the EPIC-Potsdam study can be obtained at https://www.dife.de/en/research/cooperations/epic-study/. All authors had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.