A comprehensive literature retrieval was performed on October 21, 2022, in two major academic databases: the Web of Science Core Collection (WoSCC) and Scopus. For the WoSCC database, the search query was defined as follows: TS = (“Mediterranean diet” OR “Mediterranean dietary pattern”) AND TS = (“Metabolic Syndrome” OR “Syndrome, Metabolic” OR “Insulin Resistance Syndrome” OR “Dysmetabolic Syndrome” OR “Reaven Syndrome” OR “Metabolic Cardiovascular Syndrome”) AND PY = (2015–2025) AND DT = (Article OR Review) AND LA = (English). For the Scopus database, the retrieval strategy was formulated as: TITLE-ABS-KEY(“Mediterranean diet” OR “Mediterranean dietary pattern”) AND TITLE-ABS-KEY(“Metabolic Syndrome” OR “Syndrome, Metabolic” OR “Insulin Resistance Syndrome” OR “Dysmetabolic Syndrome” OR “Reaven Syndrome” OR “Metabolic Cardiovascular Syndrome”) AND PUBYEAR > 2014 AND PUBYEAR < 2026 AND (LIMIT-TO(DOCTYPE, “ar”) OR LIMIT-TO(DOCTYPE, “re”)) AND (LIMIT-TO(LANGUAGE, “English”)). Following the removal of duplicate entries and irrelevant documents, 1723 and 1,061 valid literatures were ultimately included from WoSCC and Scopus, respectively. Complete records (including citation information) from WoSCC were exported in plain-text format, while full records with citations from Scopus were exported in CSV format to ensure data integrity. Since the core analysis of this study primarily relies on data from the WoSCC database, the detailed retrieval strategy and data filtering process for this database are elaborated below.

Due to the inherent differences in data structures between WoSCC and Scopus, direct merging would lead to the loss of key information. Therefore, the data from the two databases were analyzed independently to ensure the reliability of the results. Notably, considering the academic quality and authority of the literature indexed in WoSCC, subsequent core analyses mainly focused on the data from this database. The analyses of Scopus data (including annual publication trends and keyword clustering) are presented in Supplementary material for reference. Data analysis tools and their specific applications were as follows: The Origin 2018 software was used for the statistical analysis of annual publication volumes. The R language Bibliometrix package¹ (version 4.3.1), VOSviewer software (version 1.6.18), and CiteSpace software (version 6.3.1.0) were employed for data visualization and scientific knowledge mapping.

VOSviewer was used to construct national collaboration networks, conduct source co-citation analysis, and perform keyword co-occurrence analysis with the following parameters: the minimum number of documents per country≥14; the minimum number of documents per institution≥10; the minimum citation count≥152 for co-citation analysis; and the keyword occurrence frequency≥15 (excluding “Mediterranean diet,” “metabolic syndrome,” and their synonyms). CiteSpace software was used to identify the top 25 documents with the strongest citation bursts. CiteSpace parameters were set as follows: time slicing (2015–2025), years per slice (1), node type (cited reference), selection criteria (top N = 50), and no clipping. The Journal Impact Factor (IF) data were obtained from the 2024 Journal Citation Reports (JCR). Figure 1 shows the flowchart for search strategy and selection process in this study.

A total of 1723 unique documents were retrieved from WoSCC. As shown in Figure 2A, the annual publication volume in this field showed an overall upward trend from 2015 to 2025, with a particularly rapid growth period from 2016 to 2018. The publication volume reached its peak in 2022, with 209 articles. This growth trend reflects the vitality and in—depth nature of research in the field. However, from 2022 to 2024, it entered an adjustment and fluctuation phase, with a slight decline in publication volume, which still remained above 180 articles. The reason for the decrease in the number of publications may be attributed to specific years and database delays. As of October 21, 2025, 124 papers had been published in the field, further contributing to the accumulation of relevant literature. After deduplication, 1,061 unique records were collected from Scopus. The trend in publication volume was consistent with that of WoSCC (Supplementary Figure S1), indicating a growing research interest in the association between MD and MetS.

Analysis of the countries of corresponding authors revealed that Spain (n = 383) had the highest number of publications, followed by Italy (n = 299), the United States (n = 184), Iran (n = 87), and China (n = 86). Spain’s leading publication output underscores its prominent position and significant contributions in the field. Additionally, among the top 10 countries, Spain (43.1%) and Australia (39.30%) had the highest proportions of multi-country publications (MCPs), indicating a strong emphasis on international cooperation and academic exchange in these two countries (Figure 2B; Table 1). Figure 3A shows that the United States serves as the collaboration hub in the field, highlighting its crucial role in advancing research. Among the top 10 publishing institutions, 7 were from Spain, with 1 each from the United States, Greece, and Italy. Spain’s Carlos III Health Institute ranked first with 175 papers, followed by the University of Navarra (Spain, 121 papers) and Harvard University (United States, 109 papers). These data indicate that research institutions in Spain place greater emphasis on investigating the effects of MD on MetS, potentially due to Spain’s status as a Mediterranean coastal country. Its dietary habits, which primarily include fruits, vegetables, fish, whole grains, legumes, and olive oil, align closely with the core components of MD (Figure 3B; Table 2).

The R language Bibliometrix package was utilized to analyze journals with the highest publication volume and citation contributions in the MD and MetS field, and graphs were plotted using the ggplot2 package. VOSviewer was employed for journal co - citation analysis.

The 1723 documents included in this study were published in 567 academic journals (Supplementary material 1). As shown in Table 2 and Figure 4A, Nutrients had the highest publication volume (n = 327, IF = 5), followed by Frontiers in Nutrition (n = 47, IF = 5.1), Antioxidants (n = 31, IF = 6.6), British Journal of Nutrition (n = 30, IF = 3), and International Journal of Molecular Sciences (n = 30, IF = 4.9). Table 3 and Figure 4B present the journals with the highest citation counts, including Nutrients (n = 5,807, IF = 5), American Journal of Clinical Nutrition (n = 4,187, IF = 6.9), British Journal of Nutrition (n = 2,185, IF = 3), The Journal of Nutrition (n = 2081, IF = 3.8), and PLoS One (n = 1970, IF = 2.6). Notably, the journal co-citation map in Figure 5 shows that Nutrients, American Journal of Clinical Nutrition, and British Journal of Nutrition are core collaboration hubs. These findings collectively demonstrate the significant influence of Nutrients in the MD and MetS research field (see Table 4).

Using the R language Bibliometrix package, we identified the top 25 most cited documents in the MD and MetS field (Table 5). The titles of these citations, along with their respective DOI, are listed in Supplementary material 2. All documents had more than 260 citations and were distributed across 23 different journals, reflecting the lack of a highly centralized research system and the potential for further exploration in the field. Notably, although Nature Reviews Endocrinology had only one document included in the top-cited list, it contributed the highest single - document citation count, indirectly confirming its authoritative influence in the field. Overall, no single journal dominates the field, and the distribution of journals is relatively scattered. The top three most cited documents were: “Global aetiology and epidemiology of type 2 diabetes mellitus and its complications,” “Primary Prevention of Cardiovascular Disease with a Mediterranean Diet Supplemented with Extra-Virgin Olive Oil or Nuts,” and “Mediterranean diet and multiple health outcomes: an umbrella review of meta - analyses of observational studies and randomized trials.” Further analysis indicated that these highly cited documents primarily focus on macro reviews of the field, lacking in - depth analysis of specific research directions.

To accurately capture the research frontiers and hotspots in the MD and MetS field, CiteSpace software was used to identify the top 25 documents with the strongest citation bursts (Figure 6). The three documents with the highest burst strengths were: (1) “Primary Prevention of Cardiovascular Disease with a Mediterranean Diet” (burst strength: 43.92); (2) “The effect of Mediterranean diet on metabolic syndrome and its components: a meta - analysis of 50 studies and 534,906 individuals” (burst strength: 21.7); (3) “Primary Prevention of Cardiovascular Disease with a Mediterranean Diet Supplemented with Extra-Virgin Olive Oil or Nuts” (burst strength: 18.24). Additionally, the three most recently published documents among the citation burst list were: (1) “Long-term secondary prevention of cardiovascular disease with a Mediterranean diet and a low-fat diet (CORDIOPREV): a randomised controlled trial”; (2) “The Mediterranean diet and health: a comprehensive overview”; (3) “Mediterranean diet and health status: Active ingredients and pharmacological mechanisms.”

Combined analysis of highly cited documents and citation burst documents revealed that as global attention to metabolic health continues to grow, MD has gained widespread academic recognition as a potential dietary intervention. This study identified three core research directions in the field: 1. The effects of MD on metabolic indicators in MetS patients, including glycemic regulation, improvement of insulin resistance, correction of dyslipidemia, and management of hypertension. 2. The role of MD in MetS-related comorbidities, including the prevention and intervention effects on cardiovascular diseases, diabetes, and NAFLD. 3. The mechanisms underlying MD’s promotion of metabolic health, focusing on the anti - inflammatory and antioxidant effects of bioactive components such as polyphenols and unsaturated fatty acids, and the improvement of vascular endothelial function.

Keyword clusters are essential for rapidly grasping the main research themes and directions in a particular area. In our study, VOSviewer was used to identify 5,762 keywords. Table 6 presents the top 10 high-frequency keywords (frequency≥207). The most frequent keyword was “cardiovascular disease” (n = 509), followed by “obesity” (n = 439), “insulin resistance” (n = 335), “risk” (n = 320), “exercise” (n = 260), and “inflammation” (n = 245). Through cluster analysis, we observe six different colored clusters in Figure 7. (1) The impact of MD adherence on MetS-related cognitive impairment (red dots), including 46 keywords such as adherence, cognitive decline, Alzheimer’s disease, and components. (2) The effects of MD on MetS-related diabetes (green dots), including 39 keywords such as diabetes, insulin resistance, fatty acids, inflammation, and nutrients. (3) The impact of MD on MetS-related cardiovascular diseases and oxidative stress (blue dots), including 34 keywords such as cardiovascular disease, endothelial dysfunction, hypertension, antioxidant, and olive oil. (4) The effects of MD on MetS-related NAFLD and hepatic metabolism (yellow dots), including 25 keywords such as non-alcoholic fatty liver disease, steatohepatitis, vitamin-e, fibrosis, and insulin sensitivity. (5) The application and efficacy of MD in different MetS populations (purple dots), including 20 keywords such as men, dietary habits, adolescents, childhood obesity, and cancer. (6) The impact of MD on MetS-related central obesity and inflammation (light blue dots), including 11 keywords such as dietary inflammatory index, abdominal obesity, waist circumference, C-reactive protein, and systemic inflammation. All keywords included in the six clusters are detailed in Supplementary material 3. Notably, keywords related to inflammation, oxidative stress, insulin sensitivity, lipids, dietary quality, nutritional components, gut microbiota, and metabolism are distributed across different clusters, and the characteristics of interaction and overlap among these clusters indicate the core research hotspots in this field.

To further expand the analytical dimensions, this study extracted 8,531 keywords from the Scopus database using VOS viewer software (Supplementary Figure S2). Current research hotspots in the field of MD and MetS mainly focus on two directions: (1) The regulatory effects of key nutritional components in MD (e.g., polyphenols, unsaturated fatty acids) on metabolic indicators, inflammatory responses, and cardiometabolic health; (2) The intervention effects and application value of MD on various metabolic diseases in different populations.

To systematically predict future research trends in the MD and MetS field, the R language Bibliometrix package was used to generate a dynamic thematic evolution map (Figure 8). Such maps can effectively track the temporal development of research topics in specific fields and clearly present the evolutionary trajectory and inherent laws of research hotspots. Based on the map analysis, we summarized the phased evolutionary path of research directions in the field: From 2015 to 2017, the core research focus was on cohort-study design and traditional cardiometabolic indicators. Emphasis was placed on changes in indicators such as high-density lipoprotein cholesterol, cardiovascular disease risk factors, and C-reactive protein. The core exploration was on the potential mechanisms of MD in cardiovascular protection. From 2018 to 2020, the research focus shifted from correlation analysis to the explanation of intervention effects and pathological mechanisms. Themes such as randomized controlled trials, dietary adherence, metabolic syndrome, obesity, and oxidative stress appeared frequently, and emerging biological targets such as gut microbiota began to attract attention. From 2021 to 2023, research directions were further refined, focusing on specific dietary components (e.g., olive oil), NAFLD, and related biomarkers. Meanwhile, in-depth exploration was conducted on the regulatory effects of dietary structure and fatty acid types on cardiometabolic health. From 2024 to 2025, research showed a trend of interdisciplinary integration, with an increasing number of studies on combined interventions of lifestyle factors such as MASLD, aerobic exercise, smoking, and dietary patterns. This indicates that the field is moving toward multidimensional intervention and precise health management to more comprehensively address the complex pathological processes of MetS.

In summary, this study systematically sorted out and clarified the core research hotspots and emerging development trends in the interdisciplinary field of MD and MetS through multidimensional comprehensive analyses, including identification of citation burst documents, keyword frequency statistics, keyword clustering analysis, and tracking of thematic dynamic evolution. Combined with the aforementioned bibliometric findings, the research hotspots in this field mainly focus on three core directions as follows: (1) Metabolic regulatory effects of MD on patients with MetS: Clarifying the specific roles and clinical application value of MD in glycemic control, insulin sensitivity, lipid metabolism, and blood pressure regulation. (2) Intervention effects of MD on MetS comorbidities and associated diseases: Focusing on the prevention, progression delay, and prognosis improvement of conditions including cardiovascular diseases, type 2 diabetes mellitus, NAFLD, and cognitive impairment. (3) Analysis of molecular regulatory mechanisms underlying MD-mediated metabolic health improvement: Further exploring the metabolic protective mechanisms of its key bioactive components (e.g., polyphenolic compounds, monounsaturated fatty acids, and omega-3 polyunsaturated fatty acids) through pathways such as anti-inflammation, anti-oxidative stress, improvement of vascular endothelial function, and regulation of gut microbiota homeostasis.

To systematically clarify the research hotspots and developmental trends of the MD in the field of MetS, this study used bibliometric analysis and data visualization methods to comprehensively collate 1723 relevant articles published in the Web of Science database between 2015 and 2025. Results showed that the number of publications in this field generally exhibited a significant upward trend, with a particularly prominent growth rate between 2016 and 2018, reflecting the continuous increase in academic attention to this interdisciplinary field. Notably, the number of relevant publications in 2022 and 2024 decreased, respectively, compared with the previous year. Two main factors account for this phenomenon: first, the impact of events occurring during a specific period—the global outbreak of COVID-19 in 2019 may have undermined the reliability of research findings, disrupted subsequent data collection and follow-up efforts, and thus impeded the smooth progress of relevant studies; second, the lag in database indexing, where some literature failed to be included in the statistical scope of the corresponding year due to delayed indexing.

In terms of international research contributions, Spain took a substantial lead with 383 papers, followed by Italy (299 papers) and the United States (47 papers). Among the top 10 institutions by publication output, 7 were from Spain, with 1 each from the United States, Greece, and Italy; notably, the Carlos III Health Institute of Spain ranked first with 175 publications. It is worth highlighting that 9 out of the top 10 institutions were located in Mediterranean coastal countries, with only 1 from the United States, indicating that Mediterranean coastal countries dominate research in this field. This phenomenon may be closely linked to geographical environments and dietary traditions: the local dietary patterns of Southern European Mediterranean coastal countries (e.g., Spain, Italy, and Greece) are highly consistent with the nutritional framework of MD, which not only facilitates the implementation of relevant studies but also improves participants’ dietary adherence more effectively.

In terms of journal distribution, the 1723 papers were published across 567 journals, with renowned journals including Nutrients, Frontiers in Nutrition, and Antioxidants contributing numerous high-quality research findings. Particularly noteworthy is that Nutrients has emerged as the core academic platform in this field; it has not only published a large volume of papers but also garnered a considerable number of citations. Its leading status not only highlights the journal’s academic influence in the field of MD and MetS but also confirms its vital role as a core dissemination vehicle for research outcomes in this domain.

By analyzing the citation frequency, citation bursts, keyword occurrence rate, keyword clustering analysis, and keyword trends in the literature, we identified three main research focuses regarding the MD and MetS. The primary focus is the regulatory effect of MD on metabolic disorders. The second focus is the interventional role of MD in MetS comorbidities and related diseases. The third research hotspot is the mechanisms by which MD promotes metabolic health.

These findings are consistent with studies on MD promoting other health outcomes (Table 7). For example, a study published by Yan et al. (22) analyzed the research dynamics in the MD and diabetes mellitus, and found that components such as olive oil, legumes, and red wine are key research hotspots and trends; the core mechanisms mainly focus on anti-inflammatory and antioxidant effects, improvement of insulin sensitivity and secretion, regulation of lipid metabolism, and modulation of gut microbiota. In addition, according to the findings of Garrido-Romero et al. (23) the health-promoting potential of compounds such as polyphenols and phenolic acids, and the role of bioactive compounds in preventing and managing chronic diseases (including cardiovascular, metabolic, and neurodegenerative diseases) by regulating inflammation, oxidative stress, and gut microbiota are research hotspots in the field of olive-derived bioactive compounds. It is evident that key nutritional components, metabolic regulation, as well as mechanisms involving anti-inflammation, antioxidation, insulin sensitivity modulation, and gut microbiota modulation, represent a consensus of research hotspots in related fields. Meanwhile, this study emphasizes that in the field of the association between MD and MetS, the research focus is more centered on the metabolic benefits of MD for MetS and its intervention effects on related complications, and at the mechanistic level, it highlights the synergistic and precise regulatory mechanisms of multiple nutritional components.

This study aims to enhance the understanding of the current development status and research hotspots in the field of MD promoting metabolic health, and explore potential research directions of great value. However, it should be noted that this study has several limitations. First, our research was restricted to reviews and articles published only in the English language, which may have led to the exclusion of certain high-quality papers. Second, our study included the WOS core nd Scopus database; other databases, such as PubMed, were not considered. As a result, the included literature production may be incomplete. Third, bibliometric analysis cannot evaluate methodological rigor, evidence level or conclusion credibility of single studies. Finally, our research only included articles published within a specific time period, which may lead to publication bias in the research results. Despite these limitations, this study still provides a comprehensive overview of the field, highlighting key issues and development trends. By comprehensively considering these factors, researchers can deeply understand the development context of the field, identify potential research directions, and use this information to guide future explorations.