The association between dietary inflammatory index and non-alcoholic fatty liver disease: A systematic review and meta-analysis

Jingjing Lin; Mengna Huang; Lina Shen

doi:10.1371/journal.pone.0345297

Peer Review History

Original SubmissionDecember 11, 2025
11 Dec 2025 Author Response Attachments Attachment Submitted filename: response.doc https://doi.org/10.1371/journal.pone.0345297.r001
26 Jan 2026 Decision Letter - Jincheng Wang, Editor Dear Dr. Lin, Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. ============================== ACADEMIC EDITOR: ============================== Please submit your revised manuscript by Mar 12 2026 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org . When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file. A letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'. A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'. An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'. If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols . Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols . We look forward to receiving your revised manuscript. Kind regards, Jincheng Wang Academic Editor PLOS One Journal Requirements: When submitting your revision, we need you to address these additional requirements. 1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at https://journals.plos.org/plosone/s/file?id=wjVg/PLOSOne_formatting_sample_main_body.pdf and https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf 2. If the reviewer comments include a recommendation to cite specific previously published works, please review and evaluate these publications to determine whether they are relevant and should be cited. There is no requirement to cite these works unless the editor has indicated otherwise. 3. Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice. Additional Editor Comments: This meta-analysis addresses a clinically relevant topic and provides novel evidence on the association between DII and liver fibrosis progression. However, several issues require attention. Data inconsistencies exist between the abstract, flowchart, and Table 1 regarding study numbers and participant totals that need verification. The substantial heterogeneity (I²=74%) is inadequately explained despite subgroup analyses, and the Discussion insufficiently addresses how variations in DII calculation methods and dietary assessment tools may have contributed. Publication bias was detected for NAFLD (Egger's p=0.014), warranting more cautious interpretation rather than the current definitive conclusions. The frailty analysis based on only two comparison groups from a single study provides insufficient evidence and should be removed or clearly designated as exploratory. The MASLD nomenclature discussion is overly lengthy and could be condensed. Language errors appear throughout, including "TGrowing" in the Introduction and inconsistent reference formatting. [Note: HTML markup is below. Please do not edit.] Reviewers' comments: Reviewer's Responses to Questions Comments to the Author 1. Is the manuscript technically sound, and do the data support the conclusions? Reviewer #1: Partly Reviewer #2: Yes ******** 2. Has the statistical analysis been performed appropriately and rigorously? -->?> Reviewer #1: Yes Reviewer #2: Yes ****** 3. Have the authors made all data underlying the findings in their manuscript fully available??> The PLOS Data policy Reviewer #1: Yes Reviewer #2: Yes ****** 4. Is the manuscript presented in an intelligible fashion and written in standard English??> Reviewer #1: Yes Reviewer #2: Yes ****** Reviewer #1: 1.The manuscript is partly technically sound, with data partially supporting the conclusions. Strengths include adherence to PRISMA (checklist provided), PROSPERO registration, comprehensive searches (PubMed, WoS, Embase, Scopus, Cochrane to July 2025), dual extraction/quality assessment (NOS scores 7-9 indicating high quality), and appropriate handling of outcomes (NAFLD, fibrosis, frailty). The pooled ORs are statistically significant, and subgroups reduce heterogeneity (e.g., I²=10% in European studies for NAFLD), supporting regional/diagnostic influences. Sensitivity analyses confirm stability, and trim-and-fill adjusts for bias without altering significance. However, high heterogeneity (I²=74% for NAFLD) persists overall, potentially due to DII calculation variations (e.g., FFQ vs. 24h recall, parameter differences), population baselines, or confounders. Publication bias (Egger's p=0.014 for NAFLD) raises concerns, though mitigated. Frailty analysis is underpowered (limited studies), limiting robustness. 2.Statistical analysis is appropriate and rigorous. 3.The authors state data supporting findings are included in the article 4.The manuscript is intelligible and in standard English. Structure follows PRISMA and language is clear, professional. Reviewer #2: The manuscript is written clearly. The results are clearly presented and justify the conclusions. However, a minor remark is as follows: - The Introduction section should contain more information regarding new nomenclature (MASLD). - The abbreviations, when first introduced, should be used consistently thereafter throughout the text. ****** what does this mean? ). If published, this will include your full peer review and any attached files. If you choose “no”, your identity will remain anonymous but your review may still be made public. Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy Reviewer #1: Yes: Zheng Xu Reviewer #2: No ******** [NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.] To ensure your figures meet our technical requirements, please review our figure guidelines: https://journals.plos.org/plosone/s/figures You may also use PLOS’s free figure tool, NAAS, to help you prepare publication quality figures: https://journals.plos.org/plosone/s/figures#loc-tools-for-figure-preparation. NAAS will assess whether your figures meet our technical requirements by comparing each figure against our figure specifications. https://doi.org/10.1371/journal.pone.0345297.r002
Revision 1
13 Feb 2026 Author Response Dear Editors and Reviewers: Thank you for your letter and for the reviewers’ comments concerning our manuscript entitled “The Association Between Dietary Inflammatory Index and Non-Alcoholic Fatty Liver Disease: A Systematic Review and Meta-Analysis”(PONE-D-25-65585). Those comments are all valuable and very helpful for revising and improving our paper, as well as the important guiding significance to our researches. We have studied comments carefully and have made correction which we hope meet with approval. Revised portion are marked in red in the paper. The main corrections in the paper and the responds to the editor and reviewer’s comments are as flowing: Responds to the editor’s comments: Editor ： 1.Comment. Data inconsistencies exist between the abstract, flowchart, and Table 1 regarding study numbers and participant totals that need verification. Response: Regarding the issue of data inconsistencies, we have thoroughly verified the number of studies and total participants in the abstract, flowchart, and Table 1. The discrepancies were mainly due to inconsistent counting of different comparison groups within the same study. We have now standardized this: the abstract and flowchart clearly report the number of independent studies (18), while Table 1 details all comparison groups (43) and their corresponding cumulative sample size (262,468 participants). 2.Comment. The substantial heterogeneity (I²=74%) is inadequately explained despite subgroup analyses Response: Regarding insufficient explanation of heterogeneity, we have added a paragraph in the discussion section systematically outlining potential sources of heterogeneity: focusing on differences in DII calculation methods (such as inconsistent parameters in FFQ versus 24-hour recalls), baseline characteristics of populations (such as age and metabolic comorbidities), and regional dietary pattern differences affecting pooled effect sizes. We have also addressed this issue in the limitations section, reminding readers to consider the impact of heterogeneity when interpreting the results. 3.Comment. The Discussion insufficiently addresses how variations in DII calculation methods and dietary assessment tools may have contributed. Response: Regarding insufficient depth in the discussion, we have rewritten the paragraph on "methodological limitations of the DII" to emphasize the impact of different dietary assessment tools and calculation methods on DII accuracy. 4.Comment. Publication bias was detected for NAFLD (Egger's p=0.014), warranting more cautious interpretation rather than the current definitive conclusions. Response: Regarding the rigor of the conclusions, we have revised the statements to "evidence suggests a possible association" and noted that "future studies are needed to adjust for methodological differences to confirm the strength of the association," aligning the conclusions with the strength of the evidence. 5.Comment. The frailty analysis based on only two comparison groups from a single study provides insufficient evidence and should be removed or clearly designated as exploratory. Response: Regarding the frailty analysis, we fully agree with your assessment. In the results section, we clearly stated: "The frailty analysis included only 2 comparison groups with a limited sample size, so the results should be interpreted with caution." We also suggested in the discussion limitations that "future studies are needed to verify the association between DII and frailty," avoiding overinterpretation of the current data. 6.Comment. The MASLD nomenclature discussion is overly lengthy and could be condensed. Response: Regarding the length of the MASLD terminology discussion, we condensed the original background explanation to a paragraph under 100 words, retaining only the key information: "Although the 2023 consensus recommends using the MASLD term, the studies included in this research all used the NAFLD definition. To maintain consistency with the original research, this study continues to use the NAFLD terminology; this difference does not affect the analysis of fatty liver disease itself." This saves space for deeper methodological discussion. 7.Comment. Language errors appear throughout, including "TGrowing" in the Introduction and inconsistent reference formatting. Response: Regarding language errors, we conducted a full manuscript proofread: correcting the spelling error in the introduction from "TGrowing" to "The growing," standardizing reference formatting (e.g., journal abbreviations, author formats), and refining awkward sentences. Additionally, we hired a native editor to polish the entire manuscript to ensure proper and fluent expression. Reviewer #1: 1.Comment. high heterogeneity (I²=74% for NAFLD) persists overall, potentially due to DII calculation variations (e.g., FFQ vs. 24h recall, parameter differences), population baselines, or confounders. Response: Regarding the high heterogeneity issue you pointed out, we have added a paragraph in the discussion section to systematically explain the potential sources of heterogeneity: we focused on analyzing the impact of differences in DII calculation methods (such as inconsistencies in parameters between FFQ and 24-hour recalls), population baseline characteristics (such as age and metabolic comorbidities), and geographic dietary patterns on the pooled effect size; meanwhile, we have addressed this issue in the limitations section, reminding readers to consider the influence of heterogeneity when interpreting the results. 2.Comment. Publication bias (Egger's p=0.014 for NAFLD) raises concerns, though mitigated. Response: Concerning the issue about publication bias, we have reinforced the relevant statements in the limitations part of the discussion: clearly indicating that the Egger test (p=0.014) suggests the presence of potential publication bias, but the effect size remains significant after correction using the trim-and-fill method (OR=1.205), indicating that the main conclusions are robust; additionally, we have added a note stating that "the bias may stem from unpublished studies with small sample sizes showing negative results." 3.Comment. Frailty analysis is underpowered (limited studies), limiting robustness. Response: Regarding the insufficiency of frailty analysis, we fully agree with your observation. In the results section, we explicitly stated: "The frailty analysis included only 2 comparison groups, with a limited sample size, so the results should be interpreted with caution"; at the same time, in the discussion of limitations, we also suggested that "future research is needed to further verify the association between DII and frailty," thereby avoiding overinterpreting the current data. 4.Comment. Statistical analysis is appropriate and rigorous. The authors state data supporting findings are included in the article. The manuscript is intelligible and in standard English. Structure follows PRISMA and language is clear, professional. Response: We express our gratitude for the affirmation of the statistical analysis methods and the recognition of the language and structure. Reviewer #2: 1.Comment. The Introduction section should contain more information regarding new nomenclature (MASLD). Response: Regarding the suggestion to supplement the introduction with background on the new nomenclature (MASLD), we have added a paragraph in the introduction detailing the origin of the term metabolic dysfunction-associated steatotic liver disease (MASLD), its key differences from NAFLD in diagnostic criteria, and explaining why this study continues to use the term NAFLD based on the literature inclusion time frame and consistency considerations. This helps readers more comprehensively understand the evolution of the terminology and its potential implications for the context of this study. 2.Comment. The abbreviations, when first introduced, should be used consistently thereafter throughout the text. Response: Regarding the suggestion on consistency in abbreviation use, we have systematically checked and revised the entire text to ensure that all abbreviations are clearly defined in the form of "full term (abbreviation)" upon first appearance (e.g., metabolic dysfunction-associated steatotic liver disease (MASLD)) and uniformly use the abbreviation in subsequent text. We tried our best to improve the manuscript and made some changes in the manuscript. These changes will not influence the content and framework of the paper. And here we did not list the changes but marked in red in revised paper. We appreciate for Editors/Reviewers’ warm work earnestly, and hope that the correction will meet with approval. Once again, thank you very much for your comments and suggestions. Attachments Attachment Submitted filename: response_auresp_1.doc https://doi.org/10.1371/journal.pone.0345297.r003
4 Mar 2026 Decision Letter - Jincheng Wang, Editor The Association Between Dietary Inflammatory Index and Non-Alcoholic Fatty Liver Disease: A Systematic Review and Meta-Analysis PONE-D-25-65585R1 Dear Dr. Lin, We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements. Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication. An invoice will be generated when your article is formally accepted. Please note, if your institution has a publishing partnership with PLOS and your article meets the relevant criteria, all or part of your publication costs will be covered. Please make sure your user information is up-to-date by logging into Editorial Manager at Editorial Manager® and clicking the ‘Update My Information' link at the top of the page. For questions related to billing, please contact billing support . If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org. Kind regards, Jincheng Wang Academic Editor PLOS One Additional Editor Comments (optional): Authors have addressed all comments. This paper can be accepted for publication. Reviewers' comments: Reviewer's Responses to Questions Comments to the Author Reviewer #1: (No Response) Reviewer #2: All comments have been addressed ******** 2. Is the manuscript technically sound, and do the data support the conclusions??> Reviewer #1: Yes Reviewer #2: Yes ****** 3. Has the statistical analysis been performed appropriately and rigorously? -->?> Reviewer #1: Yes Reviewer #2: Yes ****** 4. Have the authors made all data underlying the findings in their manuscript fully available??> The PLOS Data policy Reviewer #1: Yes Reviewer #2: Yes ****** 5. Is the manuscript presented in an intelligible fashion and written in standard English??> Reviewer #1: Yes Reviewer #2: Yes ****** Reviewer #1: 1.The manuscript is generally technically sound, with a clear methodology following PRISMA guidelines and PROSPERO registration. The data from 18 studies (262,468 participants) support the main conclusions, showing a positive association between higher DII scores and increased risk of NAFLD (OR = 1.33, 95% CI: 1.23–1.44) and fibrosis (OR = 1.36, 95% CI: 1.20–1.54). Subgroup analyses identify sources of heterogeneity (e.g., geographic region and diagnostic criteria), and sensitivity analyses confirm result stability. 2.The statistical analysis is appropriate and rigorous. 3.The authors state that all data supporting the findings are included within the article. 4.The manuscript is intelligible and written in standard English. Reviewer #2: The Authors have made corrections according to the Reviewer's suggestions and improved the manuscript. ****** what does this mean? ). If published, this will include your full peer review and any attached files. If you choose “no”, your identity will remain anonymous but your review may still be made public. Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy Reviewer #1: Yes: Zheng Xu Reviewer #2: No ******** https://doi.org/10.1371/journal.pone.0345297.r004
Formally Accepted
Acceptance Letter - Jincheng Wang, Editor PONE-D-25-65585R1 PLOS One Dear Dr. Lin, I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS One. Congratulations! Your manuscript is now being handed over to our production team. At this stage, our production department will prepare your paper for publication. This includes ensuring the following: * All references, tables, and figures are properly cited * All relevant supporting information is included in the manuscript submission, * There are no issues that prevent the paper from being properly typeset You will receive further instructions from the production team, including instructions on how to review your proof when it is ready. Please keep in mind that we are working through a large volume of accepted articles, so please give us a few days to review your paper and let you know the next and final steps. Lastly, if your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org. You will receive an invoice from PLOS for your publication fee after your manuscript has reached the completed accept phase. If you receive an email requesting payment before acceptance or for any other service, this may be a phishing scheme. Learn how to identify phishing emails and protect your accounts at https://explore.plos.org/phishing. If we can help with anything else, please email us at customercare@plos.org. Thank you for submitting your work to PLOS ONE and supporting open access. Kind regards, PLOS ONE Editorial Office Staff on behalf of Dr. Jincheng Wang Academic Editor PLOS One https://doi.org/10.1371/journal.pone.0345297.r005

Open letter on the publication of peer review reports

PLOS recognizes the benefits of transparency in the peer review process. Therefore, we enable the publication of all of the content of peer review and author responses alongside final, published articles. Reviewers remain anonymous, unless they choose to reveal their names.

We encourage other journals to join us in this initiative. We hope that our action inspires the community, including researchers, research funders, and research institutions, to recognize the benefits of published peer review reports for all parts of the research system.

Learn more at ASAPbio .