Title: Association between Healthy Eating Index-2015 scores and metabolic syndrome among
Iranian women: A cross-sectional study
Version: 0 Date: 20 Jul 2023
Reviewer:  Mahbanoo Farhadi
Reviewer's report:
I hope this letter finds you well. I have had the opportunity to thoroughly review your article
titled "Association between Healthy Eating Index-2015 Scores and Metabolic Syndrome among
Iranian Women: A Cross-Sectional Study." I appreciate the importance of investigating the
relationship between diet quality and metabolic syndrome (MetS) in the context of Iranian
women, and I commend your efforts in conducting this cross-sectional study.
The purpose of your article is to identify the association between the Healthy Eating Index (HEI)
and components of MetS among female teachers in Qom city, Iran. This objective highlights the
significance of understanding the impact of diet quality on MetS, which is a prevalent public
health issue worldwide. By focusing specifically on Iranian women, your study addresses a
population that is underrepresented in the existing literature, providing valuable insights into the
relationship between diet and MetS in this specific demographic.
To further strengthen your research, I would suggest considering the following points:
Abstract
From a reviewer's point of view, the abstract provides a clear overview of the study's objectives,
methods, results, and conclusions. However, there are a few suggestions to enhance its clarity:
1. The background section could provide brief context on the prevalence or impact of Metabolic
Syndrome (MetS) globally or in Iran. This would help readers understand the significance of
studying the association between the Healthy Eating Index (HEI) and MetS.
2. The methods section provides a good summary of the study design and tools used. However,
it would be helpful to mention the duration of data collection or specify the period during which
the study was conducted.
3. The abstract mentions several associations between specific HEI-2015 components and
MetS. To enhance clarity, it could specify if these associations were statistically significant by
including p-values or confidence intervals.
4. For the conclusion section, it could be strengthened by briefly summarizing the main findings
of the study. For instance, a statement like "Higher HEI-2015 scores, particularly in total
vegetables, dark green vegetables, and beans, as well as lower scores in fatty acid ratio, refined
grain, and added sugars, were found to be associated with reduced odds of having MetS among
Iranian women teachers."
Overall, the abstract provides a good overview of the study. Adding some clarifications and
summarizing the key findings would enhance its effectiveness.
Introduction
1. In the sentence "Numerous definitions of MetS have been proposed by the World Health
Organization (WHO), the World Diabetes Federation, and the American Heart Association
(AHA) [1, 2]," it would be useful to mention the year(s) of the references in the brackets.
2. The sentence "According to the ATP III, the existence of three or more criteria indicates
the MetS including high blood glucose (more than 100 mg/dl in the fasting state), abdominal
obesity (waist circumference (WC) more than 88 cm in women and 102 cm in men), high-
density lipoprotein cholesterol (HDL-C) levels less than 50 mg/dl in women and less than 40
mg/dl in men, triglyceride (TG) level more than 150 mg/dl, and high blood pressure (systolic
blood pressure (SBP) greater than 130 mmHg or diastolic blood pressure (DBP) greater than 85
mmHg) [3]" could be divided into multiple sentences for better readability.
.
3. The statement "Since foods and macro- /micronutrients are not commonly consumed alone,
investigating the dietary patterns makes it possible to study the impact of the whole diet on MetS
and its components which provides a practical approach for dietary recommendations and MetS
management" could be rephrased to improve clarity. For example: "Due to the fact that foods
and macro- /micronutrients are rarely consumed in isolation, studying dietary patterns allows us
to examine the overall impact of the entire diet on MetS and its components, thereby providing
a practical approach for dietary recommendations and MetS management."
4. In the sentence "It has been shown that the highest level of adherence to the HEI is significantly
associated with a reduced risk of cardiovascular disease, cancer, type 2 diabetes mellitus, and
all-cause mortality [14]. However, a cohort study failed to indicate any significant association
between adherence to the HEI and the risk of type 2 diabetes [15]," it would be helpful to provide
a brief explanation of the findings of the cohort study to maintain coherence.
Overall, the introduction effectively provides an overview of the research background, highlights
the significance of studying diet quality in relation to MetS, and sets the stage for the specific
aim of the study.
Methods
1. Participants: The section provides a clear description of the study participants, specifying
that the study included non-menopausal women teachers aged 30 to 55 years in 2018-2019.
However, it would be helpful to include information regarding how the age range was chosen
and the rationale behind including non-menopausal women.
2. Sample Size and Sampling: The section mentions that the sample size was estimated to be
97 participants based on power calculations and the consideration of variables such as HDL-
C and healthy eating index. However, there is no further discussion regarding how the final
sample size of participants was determined. It would be helpful to provide more details about
the sample size estimation process and the selection of participants using multistage cluster
sampling. Additionally, information regarding the response rate and any considerations for
potential selection bias should be mentioned.
3. Data Collection: The section provides a detailed description of data collection methods,
including the use of questionnaires, anthropometric measurements, and clinical and biochemical
examinations. However, it would be valuable to include information about the training and
qualifications of the individuals who collected the data to ensure standardization and reliability.
Additionally, more information regarding the specific methods used for measuring blood
pressure, HDL-C, TG, and fasting plasma glucose would be beneficial.
4. Dietary Assessment: The section describes the use of a Food Frequency Questionnaire (FFQ)
to assess participants' dietary intake over the past year. It is mentioned that the validity and
reliability of the FFQ for the Iranian population have been confirmed previously. However, no
information is provided on the specific validation studies or any limitations associated with the
FFQ. It would be helpful to include references or additional details to support the validity and
reliability of the FFQ.
5. Statistical Analysis: The section states that the normal distribution of data was checked, but it
does not mention the specific tests used or the criteria for determining normality. Providing more
information on the statistical tests employed and appropriate references would be beneficial.
Additionally, it would be valuable to specify the software or statistical package used for the
analyses and provide version information.
6. Presentation of Results: The section mentions that data were presented as mean ± Standard
Error (SE), but it does not specify whether these were means of continuous variables or
proportions for categorical variables. Clarifying the variables and providing information about
the use of percentages or proportions for categorical variables would enhance the clarity of
reporting.
7. Limitations: The methods section does not explicitly mention potential limitations of the
study. It is important to include a brief discussion of potential limitations, such as the potential for
recall bias in dietary assessment, selection bias in the sampling process, or limitations associated
with the measurement methods used.
Overall, the methods section provides a detailed description of the study design and data
collection procedures. However, some additions and clarifications, as mentioned above, would
enhance the understanding and strengthen the methodology presentation.
Results
1. Subject's characteristics: The section provides a clear summary of the characteristics of the
study participants, including the sample size (97 women teachers) and their mean age (43.87 ±
7.14 years). The presentation of the participants' characteristics in Table 2 is helpful in providing
an overview. However, it would be beneficial to include additional relevant demographic
information, such as marital status and educational background, if collected
.
2. Association of HEI components with metabolic markers: The section presents the scores
of HEI components and the HEI total score for women with and without MetS, indicating
which components had the highest and lowest scores. This information is clear and helpful for
understanding the dietary patterns of the participants. However, it would be useful to include
the specific units or scales used for scoring the HEI components to enhance clarity.
3. Multivariable-adjusted ORs for MetS risk: The section reports the odds ratios (ORs) and
confidence intervals (CIs) for the relationship between HEI components' scores and MetS risk.
The use of ORs and CIs is appropriate for assessing associations. However, it would be helpful
to clarify what is meant by "crude model" and "adjusted model" in the context of the statistical
analysis. Additionally, it would be valuable to provide the specific variables that were included
in the adjusted model for controlling confounding factors.
4. Presentation and interpretation of results: The presentation of the results in tables and the
description of significant findings are clear. However, it would be beneficial to provide the actual
values or means (in addition to standard deviations) for the significant associations reported.
This would allow readers to better understand the magnitude of the associations.
Overall, the Results section provides a clear overview of the study findings, with relevant
statistical analyses and comparisons between groups. The presentation could be enhanced by
providing additional demographic information, specifying the units or scales used for scoring
HEI components, and providing the actual values or means for significant associations.
Discussion
1. Introduction and contextualization: The section provides a clear introduction to the topic,
highlighting the significance of metabolic syndrome (MetS) and the role of diet in its
management. The mention of previous studies linking dietary quality to metabolic health adds
relevance to the study. However, it would be beneficial to provide a brief overview of the
characteristics and complications of MetS to provide context for readers who may be less
familiar with the topic
.
2. Comparison with previous studies: The discussion compares the findings of the present
research with previous studies in various populations. The inclusion of studies conducted on
different age groups and populations adds depth to the discussion. However, it would be helpful
to include more context about the similarities and differences in study methodologies, sample
sizes, and study populations, as these factors can impact the comparability of the results.
3. Specific findings and associations: The section discusses the specific associations found
in the study related to the components of HEI-2015 and MetS. The inclusion of specific
dietary components, such as total vegetables, dark green vegetables and beans, poly- and
monounsaturated fatty acids, refined grains, and added sugars, provides clarity about the
relationship between diet and MetS. The discussion also acknowledges contradictory findings
from other studies, providing a balanced view of the existing evidence. However, it would be
useful to discuss potential mechanisms or biological explanations for the observed associations,
such as the role of fiber, phytochemicals, and antioxidants in fruits, vegetables, and whole grains.
4. Limitations and strengths: The section mentions the limitations of the study, including
the cross-sectional nature, memory based FFQ questionnaires, and potential confounding
variables. The acknowledgment of these limitations demonstrates an awareness of the study's
shortcomings. The mention of strengths, such as data analysis adjustments, valid questionnaires,
and trained nutritionists, adds credibility to the study. However, it would be beneficial to
discuss further potential sources of bias or limitations specific to the study population of women
teachers.
5. Generalizability: The section acknowledges that the findings may not apply to all women
populations or males due to the specific investigation of women teachers. This consideration
adds transparency to the study's scope and enhances the reader's understanding of the
generalizability of the findings. However, it would be helpful to briefly discuss the potential
implications or relevance of the findings to the broader population, highlighting the importance
of further research in different populations.
Overall, the Discussion section effectively discusses the study's findings, compares them with
previous studies, acknowledges limitations, and provides an insightful analysis. It could be
strengthened by providing a brief background on MetS, including potential mechanisms behind
the observed associations, discussing additional sources of bias or limitations specific to the
study population, and briefly outlining the implications of the findings for a broader population.
Conclusion
Overall, the conclusion section appears to be concise and provides a clear statement regarding the
relationship between the Healthy Eating Index-2015 (HEI-2015) score and metabolic syndrome
(MetS) among Iranian women. However, there are a few areas that could be improved or
expanded upon:
1. The conclusion could benefit from a brief summary of the key findings of the study. This
would help the reader better understand the context and significance of the conclusion.
2. While it is mentioned that the HEI-2015 score is an "appropriate predictor" for the relationship
between diet quality and MetS, it would be helpful to elaborate on what makes it appropriate.
Are there specific components of the HEI-2015 that align with the risk factors for MetS?
3. The conclusion states that prospective cohort studies are required to confirm the findings.
It would be helpful to provide a brief explanation of why such studies are necessary and what
additional insights they could provide. This would strengthen the conclusion and provide a clear
direction for future research.
4. Consider mentioning any limitations or potential shortcomings of the study in the conclusion.
This would help to address potential criticism or questions that may arise from readers.
Overall, the conclusion could be made more impactful by providing a concise summary of the
key findings, elaborating on why the HEI-2015 score is an appropriate predictor, explaining the
need for prospective cohort studies, and addressing any identified limitations.