Exercise and Nutrition as Epigenetic Regulators of Gene Expression: An Exploratory Scoping Review with Bibliometric Analysis

Abstract

Background: Epigenetic processes are increasingly discussed as a potential interface between environmental exposures and genomic function. However, systematic integration and forward looking synthesis of how exercise and nutrition, conceptualised as modifiable lifestyle interventions, are studied in relation to epigenetic contexts and associated health outcomes remains limited. Objective: This study maps and summarises the scope of existing evidence on combined interventions of exercise and nutrition in relation to epigenetic contexts and related health outcomes using a scoping review and bibliometric analysis. It identifies research hotspots and knowledge gaps and characterises the developmental trajectory of the field, with particular attention to its current exploratory stage and future research directions. Methods: This scoping review followed the five stage framework proposed by Arksey and O’Malley. A systematic search was conducted in PubMed, Web of Science, Scopus, EMBASE, and MEDLINE from database inception to 5 October 2025. Bibliometric and visualisation analyses were performed using CiteSpace, VOSviewer, and the R bibliometrix package to examine collaboration networks, thematic clusters, and research trends across countries, institutions, authors, and keywords. Results: Seventeen studies involving 1,568 participants were included, with randomised controlled trials representing the predominant design. Across specific populations and sampled tissues, most commonly blood and skeletal muscle, combined interventions were reported in association with changes in DNA methylation, histone modifications, and non coding RNAs. These epigenetic observations were described alongside metabolic indicators, muscle related outcomes, inflammatory markers, and ageing related measures. The evidence base remains heterogeneous and largely exploratory. Bibliometric analysis suggests geographically concentrated publication output. Keyword clustering identified three thematic domains, intervention strategies, mechanistic exploration, and health outcomes, while tissue specific responses and epigenetic clocks emerged as areas of growing interest. Conclusion: Combined interventions of exercise and nutrition demonstrate exploratory associations within epigenetic contexts and related health dimensions. Given the limited scale and heterogeneity of current studies, the literature should be interpreted as hypothesis generating. Future research may benefit from standardised assessment approaches, longitudinal and multi tissue designs, multi omics integration, and broader international collaboration to support validation focused investigation rather than immediate predictive application.