Review for 10.1186/s12876-025-03834-x (2025)

Title: Association Between Non-Skimmed Milk Consumption and Metabolic Dysfunction-
Associated Fatty Liver Disease in US Adults: Insights from NHANES Data
Version: 1 Date: 09 Mar 2025
Reviewer:  Amira A. A. Othman
Reviewer's report:
First of all
I want to congratulate the authors on their work. In this study, Wu et al. investigate
the association between the frequency of non-skimmed milk product consumption and the
prevalence of non-alcoholic fatty liver disease (NAFLD) using data from the National Health
and Nutrition Examination Survey (NHANES). The study aims to determine whether frequent
consumption of non-skimmed milk products is associated with an increased risk of NAFLD and
whether this association is influenced by demographic and lifestyle factors such as education
level, age, and BMI. The findings aim to provide insights into dietary modifications that could
help prevent or manage NAFLD..
Non-alcoholic fatty liver disease (NAFLD) is recognized as the most prevalent chronic liver
disease, impacting about 30% of global individuals, with the potential to progress to advanced
hepatic fibrosis and end-stage liver diseases eventually [*]. In June 2023, a multi-society
committee of international experts was gathered, and new terminology was adopted to reduce
stigma and increase disease awareness [**]. A new terminology, Steatotic liver disease (SLD),
replaces “fatty liver disease” as the umbrella term. Under subgroups of SLD, NAFLD has been
renamed as metabolic dysfunction-associated Steatotic liver disease (MASLD) [**]. NAFLD/
MASLD is closely related to metabolic syndrome (MetS) and its associated components of
hypertension, type 2 diabetes mellitus, dyslipidemia, and obesity[***].
(*:doi: 10.1097/HEP.0000000000000004, **: doi: 10.1016/j.jhep.2023.06.003, ***  doi:
10.1111/apt.17308).
The authors handled the reviewer comments satisfactorily, nevertheless, there is an observation
for which sufficient justification must be obtained.
In general:
1. The writing quality needs improvement, and it would be beneficial to consult an English
language expert to address spelling and grammatical issues throughout the text.
2. Abbreviations must be fully written on their first appearance.
In Title:
1. The title should be more informative and concise. , I suggest “ Association Between Non-
Skimmed Milk Consumption and Metabolic Dysfunction-Associated Fatty Liver Disease in US
Adults: Insights from NHANES Data”.
In the Abstract section
2. The background subsection in the abstract :
3. It should be the shortest part of the abstract. It should briefly outline the following information:
What is already known about the subject related to the paper in question? What is unknown
about the subject and what the study intended to examine (or what the paper seeks to present)?
4.  The type of study: a population-based study.
5. In the method subsection of the abstract, summarize analytical approaches.
6. In the results subsection in the abstract, include specific numerical results from the NHANES
analysis (e.g., odds ratios, p-values) and briefly mention the key findings from the subgroup
analysis, such as the influence of education level on the association between milk consumption
and MAFLD.
7. In the conclusion subsection in the abstract, clarify the clinical implications of the findings.
In the Introduction section:
8. Try to provide a summarized description of The National Health and Nutrition Examination
Survey (NHANES) in the background section. You may use the following: “NHANES
(www.cdc.gov/nchs/nhanes) is designed to assess the health and nutritional status of adults
and children in the United States. The survey is distinctive in that it incorporates both
physical examinations and interviews. Several cross-sectional, nationally representative health
examination surveys are part of the NHANES program. Questions about demographics,
health insurance status, dietary habits, acute and chronic medical issues, mental health, and
prescription drug use are all included in the health interview. Exam components can change
between survey cycles but typically include blood pressure, dental exams, vision, hearing,
dermatology, fitness, balance and strength testing, respiratory testing, taste and smell, and
body measurements (weight, height, skin folds, body composition scans). Hematology, organ
and endocrine function (e.g., thyroid, kidney), environmental exposure, dietary biomarkers,
metabolic and cardiovascular health, and infectious disease are a few examples of laboratory
components.”.Briefly mentioning the novelty of using NHANES data to explore this association.
9. MAFLD must replace NAFLD:  “In contrast to NAFLD, MAFLD does not necessitate ruling
out other liver disease causes, such as viral hepatitis or heavy alcohol use*. The new name
chosen to replace NAFLD reflected the disease etiology better and conveyed a more practical
approach in daily clinical practice than NAFLD, considering its close association with metabolic
syndrome**. Please discuss the new nomenclature in more detail.
(*: Doi: 10.1016/j.jhep.2020.03.039, **: doi: 10.1097/HEP.0000000000000520)
10. Providing a clearer rationale for why non-skimmed milk consumption is an important factor
to study about MAFLD.
In the Methods section:
11. The exclusion criteria and the handling of missing data: Provide a more detailed explanation
of how missing data were handled and justify the exclusion criteria..
12. Briefly discuss the limitations of self-reported dietary data and the CAP method.
13. Provide more details on the validation process for the core targets, including any cross-
validation with external datasets.
14. Discuss why HepG2 cells were chosen and how the treatment conditions (e.g., 20 µM for
24 hours) were determined.
15. The use of the Controlled Attenuation Parameter (CAP) to diagnose MAFLD is well-
justified, but the authors should briefly discuss the limitations of this method compared to more
direct measures like liver biopsy.
16. Discuss how multiple comparisons were handled and whether any adjustments were made
to control for Type I error.
In the Results section:
17. In all tables, please explain the abbreviations under the tables.
18. Ensure that table captions succinctly describe the content for standalone clarity.
19. Summarize key numerical findings in the text before directing the reader to tables/figures.
20. provide more details on the baseline characteristics of the NHANES participants, especially
any differences between those with and without MAFLD.
21. The authors should provide more details on the subgroup analysis, particularly the interaction
between milk consumption and education level.
22. Discuss the clinical significance of the findings, not just statistical significance.
In the Discussion section:
23. The discussion section is one of the final parts of a research paper, in which an author
describes, analyzes, and interprets their findings. They explain the significance of those results
and tie everything back to the research question(s). In this manuscript, there is confusion
between what should be written in the introduction and discussion sections. Please reconstruct
the discussion section.
24. The discussion could benefit from a more in-depth exploration of why non-skimmed milk
consumption might be associated with NAFLD, including any potential biological mechanisms.
25. Discuss the novelty of your study regarding previously published papers.
26. Discuss the implications of their findings for clinical practice,
27. What are the study limitations? particularly the small sample size in the NHANES analysis
and the potential for bias due to missing data, as well as cross-sectional design, which precludes
causal inference.
In the Conclusion section:
28. You should emphasize the need for urgent public health action.
29.  Be more specific about the clinical implications of the findings.
30. Highlight the need for further research, particularly longitudinal studies.