The Mediterranean Diet and Inflammatory Bowel Disease: A Comprehensive Systematic Review and Meta-Analysis of Efficacy

The Mediterranean Diet and Inflammatory Bowel Disease: A Comprehensive Systematic Review and Meta-Analysis of Efficacy | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article The Mediterranean Diet and Inflammatory Bowel Disease: A Comprehensive Systematic Review and Meta-Analysis of Efficacy Muhammad Shahzil, Syeda Kanza Kazmi, Minahel Shehzadi, Fariha Hasan, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7035116/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Introduction: Environmental and dietary factors significantly influence the development and progression of inflammatory bowel disease (IBD). The Mediterranean diet (MD), characterized by high consumption of fruits, vegetables, healthy fats, and lean proteins and low intake of processed foods and sugars, is frequently recommended as an adjunctive therapy. The American Gastroenterological Association includes MD in its guidelines for managing Crohn's disease (CD); however, the recommendation strength is low due to the DINE-CD trial, which did not demonstrate superiority of MD compared to the specific carbohydrate diet. This meta-analysis aims to enhance current data by evaluating existing research on dietary management in ulcerative colitis (UC) and assessing the effectiveness of MD in achieving symptomatic remission or improvement in IBD patients compared to other dietary interventions. Methods: Following Cochrane and PRISMA guidelines We compared the MD to alternative dietary interventions in IBD patients Randomized controlled trials (RCTs) were identified through comprehensive database searches up to October 2024. Data were analyzed using RevMan Web, employing a random-effects model. Results: Four RCTs involving a total of 339 IBD patients were included in this analysis. Among these, 167 patients (including those with UC and CD) received the Mediterranean diet, while 172 followed non-Mediterranean diets (NMD). The MD was associated with a statistically significant improvement in clinical remission compared to NMD (RR 1.18, P = 0.02). When compared specifically to a regular diet, MD significantly reduced both CRP levels (MD -2.66, P < 0.00001) and fecal calprotectin (MD -229.46, P = 0.008). Specifically, within the UC population, MD significantly decreased CRP and fecal calprotectin levels. Discussion: Our findings suggest the Mediterranean diet provides significant benefits in managing IBD, particularly for UC patients, demonstrated by notable reductions in CRP and fecal calprotectin levels. However, similar benefits in patients with CD remain less clear despite previous evidence of symptomatic improvement. Although MD shows superiority over regular diets, its relative advantage compared to other specialized diets, such as the specific carbohydrate diet (SCD), remains uncertain. Variability among studies and adherence challenges complicate these comparisons. Future research should aim to identify specific patient subgroups most likely to benefit from MD and strategies to enhance adherence. Inflammatory Bowel Diseases Mediterranean Diet Ulcerative Colitis Crohn Disease Remission Induced C-Reactive Protein Calprotectin Full Text Additional Declarations Competing interest reported. Kofi Clarke discloses receiving clinical trial support from Takeda. All other authors declare no conflicts of interest related to the research, authorship, or publication of this manuscript. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7035116","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":481768492,"identity":"28b8bb54-b865-4020-a715-59e5f3ad9042","order_by":0,"name":"Muhammad Shahzil","email":"data:image/png;base64,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","orcid":"","institution":"Penn State Health Milton S. 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The Mediterranean diet (MD), characterized by high consumption of fruits, vegetables, healthy fats, and lean proteins and low intake of processed foods and sugars, is frequently recommended as an adjunctive therapy. The American Gastroenterological Association includes MD in its guidelines for managing Crohn's disease (CD); however, the recommendation strength is low due to the DINE-CD trial, which did not demonstrate superiority of MD compared to the specific carbohydrate diet.\u003c/p\u003e\n\u003cp\u003eThis meta-analysis aims to enhance current data by evaluating existing research on dietary management in ulcerative colitis (UC) and assessing the effectiveness of MD in achieving symptomatic remission or improvement in IBD patients compared to other dietary interventions.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFollowing Cochrane and PRISMA guidelines We compared the MD to alternative dietary interventions in IBD patients Randomized controlled trials (RCTs) were identified through comprehensive database searches up to October 2024. Data were analyzed using RevMan Web, employing a random-effects model.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFour RCTs involving a total of 339 IBD patients were included in this analysis. Among these, 167 patients (including those with UC and CD) received the Mediterranean diet, while 172 followed non-Mediterranean diets (NMD). The MD was associated with a statistically significant improvement in clinical remission compared to NMD (RR 1.18, P = 0.02). When compared specifically to a regular diet, MD significantly reduced both CRP levels (MD -2.66, P \u0026lt; 0.00001) and fecal calprotectin (MD -229.46, P = 0.008). Specifically, within the UC population, MD significantly decreased CRP and fecal calprotectin levels.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDiscussion:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eOur findings suggest the Mediterranean diet provides significant benefits in managing IBD, particularly for UC patients, demonstrated by notable reductions in CRP and fecal calprotectin levels. However, similar benefits in patients with CD remain less clear despite previous evidence of symptomatic improvement.\u003c/p\u003e\n\u003cp\u003eAlthough MD shows superiority over regular diets, its relative advantage compared to other specialized diets, such as the specific carbohydrate diet (SCD), remains uncertain. Variability among studies and adherence challenges complicate these comparisons. Future research should aim to identify specific patient subgroups most likely to benefit from MD and strategies to enhance adherence.\u003c/p\u003e","manuscriptTitle":"The Mediterranean Diet and Inflammatory Bowel Disease: A Comprehensive Systematic Review and Meta-Analysis of Efficacy","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-07-08 14:16:54","doi":"10.21203/rs.3.rs-7035116/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"974e8c0a-9089-44fc-a4a8-ffe3f4b99c00","owner":[],"postedDate":"July 8th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-07-08T14:16:56+00:00","versionOfRecord":[],"versionCreatedAt":"2025-07-08 14:16:54","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7035116","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7035116","identity":"rs-7035116","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}