Healthy Japanese Dietary Pattern Is Associated with Slower Biological Aging in Older Men: WASEDA'S Health Study

Aging is the greatest risk factor for numerous diseases and mortality, and establishing geroprotective interventions targeting aging is required. Previous studies have suggested that healthy dietary patterns, such as the Mediterranean diet, are associated with delayed biological aging; however, these associations depend on nationality and sex. Therefore, this study aimed to investigate the relationship between dietary patterns identified through principal component analysis and biological aging in older men of Japan, one of the countries with the longest life expectancies. Principal component analysis identified two dietary patterns: a healthy Japanese dietary pattern and a Western-style dietary pattern. Seven epigenetic clocks, some of the most accurate aging biomarkers, were identified using DNA methylation data from whole-blood samples. Correlation analyses revealed that healthy Japanese dietary patterns were significantly negatively or positively correlated with multiple epigenetic age accelerations (AgeAccel), including AgeAccelGrim, FitAgeAccel, and age-adjusted DNAm-based telomere length (DNAmTLAdjAge). Conversely, the Western-style dietary pattern showed no significant correlation with any of the examined epigenetic AgeAccels or age-adjusted values. After adjusting for confounders, the healthy Japanese dietary pattern remained significantly negatively correlated with AgeAccelPheno and AgeAccelGrim and positively correlated with DNAmTLAdjAge. These findings suggest that a Western-style dietary pattern is not associated with biological aging, whereas a healthy Japanese dietary pattern is associated with delayed biological aging in older Japanese men. Our findings provide evidence that healthy dietary patterns may have beneficial effects on delayed biological aging in older Japanese men. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This research was supported by Grant-in-Aid for Early-Career Scientists (20K19520) from the Japan Society for the Promotion of Science. This project is a collaborative research project with the Institute of Stress Science, Public Health Research Foundation. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The Research Ethics Committee of Waseda University (approval numbers: 2014-G002 and 2018-G001) I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes The measurement data used to support the findings of this study are available from the corresponding author upon reasonable request.