Sugar-Sweetened Beverage (SSB) Intake Is Associated with Non-SSB Diet Quality in Swiss Adults

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

General Comments

This manuscript provides nationally representative evidence on the association between sugar-sweetened beverage (SSB) intake and overall diet quality excluding beverages among Swiss adults. Overall, the study addresses an important public health nutrition topic and is based on robust national dietary data. However, several aspects of the discussion would benefit from further clarification and strengthening to enhance the manuscript’s public health relevance.

 

Specific Comments

1. Lines 235–242:
   The discussion in this section remains largely descriptive and focuses primarily on statistical interpretation. The authors are encouraged to expand this section by incorporating potential cultural, dietary, or public health explanations to better contextualize the observed differences across linguistic regions.
2. Lines 243–246:
   The age-group differences described are not sufficiently interpreted from a health inequality or life-course perspective. The authors should consider whether the higher SSB consumption observed among younger adults may reflect broader social or environmental determinants and discuss the implications for the timing and targeting of public health interventions.
3. Lines 258–262:
   While the manuscript reports findings related to AHEI components, the discussion does not sufficiently address the suitability of the AHEI as a tool for public health monitoring or its alignment with Swiss dietary guidelines. Brief clarification on these points would strengthen the public health applicability of the results.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Although the topic is relevant, the manuscript requires substantial work to reach a publishable level. Overall, more detail is needed on how the data were analyzed, with clearer reporting of the statistical analysis. A full language revision is also recommended, since in some parts the writing interferes with understanding.

1. The abstract is long and heavy with data and information, but it lacks interpretation and the main ideas of the results and conclusions. Reporting coefficients with confidence intervals is not necessary in the abstract. It is more important to interpret the results and explain what they mean in direction and magnitude.Line 43: Using the word convincing to describe previous literature is too generic. The authors should explain in the introduction why that previous literature is convincing.

2. Lines 59 to 67: The introduction lacks a better characterization of the problem. The authors mention that Swiss people consume more sugar sweetened beverages than recommended, but they do not report consumption levels. Including this information would help justify the importance of the study.

3. Section 2.1 would benefit from a language revision. Also, it is not necessary to mention all stages and the number of participants at each stage of the data collection process in the main text. This information could be moved to the supplementary materials.

4. Line 84: Please improve the sentence to make its meaning clearer. It would also be useful to indicate when the study started and finished, including date or year, to clarify the timeline.

5. Lines 93 to 96: Please expand on what is meant by extended and explain how it was extended. This is important because this calculation generates the final variable used in the analysis.

6. Lines 102 to 104: Why do you multiply by 4? Please provide a justification and a citation. If there is no reference, please explain the reason for this multiplication.

7. I recommend modifying Table 1. In its current form it looks crowded and includes too much information that is not described or used in further analysis. I suggest reporting only the count or the weighted percentage in the Results section. The full table could be included in the supplementary material.

8. The table reports medians, but the footnote mentions average. Please confirm which statistic is presented and be consistent throughout the document.

9. Tables 1 and 2 have very short descriptions. Please expand them.

10. Table 2 is the main result of the study and is explained too briefly. Although Figure 1 expands on the table, there are still variables that would be interesting to present and explain further, such as gender, income, or body mass index.

11. I suggest adding the coefficients for the full regression, not only the three main groups presented.

12. Lines 204 to 209: The authors mention that diet scores are low, but the manuscript does not explain what is considered a low or high score. This makes it difficult to interpret the statement.

13. The authors mention sugar sweetened beverage consumption in Switzerland and state that it is lower than in the United States, but they do not mention magnitudes. Including magnitudes would help contextualize the problem and the differences.

14. Line 227: Please clarify which results are being referenced and how they compare.

15. Please be cautious when comparing studies. It is not clear whether previous studies also evaluated diet quality excluding sugar sweetened beverages. If not, the results are not directly comparable. Please clarify this point.

16. Line 246: The sentence is confusing. It is not clear what potential is referring to.

17. Lines 252 to 257: The cited study is related, but the current wording does not clearly justify citing the authors’ own work. The idea should be strengthened so that the self citation is better justified.

18. Lines 259 to 261: These results are not shown or mentioned earlier, so it is difficult to understand them in the Discussion section.

19. Line 279: Like what? Please explain how future research would improve this.

Comments on the Quality of English Language

A full language revision is also recommended, since in some parts the writing interferes with understanding.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Nowadays when chronic non-communicable diseases are increasing and obesity is considered an independent risk factor for their development, it is particularly important for research to focus on elements of dietary patterns that contribute to excessive energy intake and consequently to obesity. In this context, sugar-sweetened beverages (SSB) are often highlighted as a source of “empty calories” whose intake warrants close monitoring and can be meaningfully linked to overall diet quality. This study addresses precisely this issue. The authors examine this timely topic using a methodologically sound approach and present the results in a systematic and clear manner. Although the overall quality of the manuscript is unquestionable, I recommend that the authors provide several methodological clarifications prior to publication.

The main methodological clarifications required relate to the distinction between confounders and mediators in the regression models (LM1 and LM2).Several variables included in the regression models particularly BMI, physical activity, and total energy intake, may lie on the causal pathway between SSB intake and non-SSB diet quality rather than acting as pure confounders. This concern is particularly relevant for Model 2 (LM2), which additionally adjusts for average daily energy intake. As shown in Table 2, the effect estimates for SSB consumer type are only marginally attenuated when moving from LM1 to LM2 (e.g., β = 2.62 vs. 2.30 for non-consumers and β = −3.16 vs. −3.16 for high consumers). While this similarity suggests robustness of the association, it also raises questions regarding the conceptual role of energy intake in the model. Clarifying whether LM2 is intended to estimate an energy-independent association or a conservative, potentially overadjusted effect would substantially strengthen the interpretation of these findings.

I encourage the authors to address the methodological clarifications outlined above, as doing so would substantially strengthen the manuscript and render it suitable for publication.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

This manuscript presents a valuable investigation into the relationship between sugar-sweetened beverage (SSB) consumption and the quality of the remaining diet (non-SSB diet quality) among Swiss adults. The study addresses an important gap in the literature, as most prior research on this specific "clustering" of unhealthy dietary behaviors has focused on North American populations. The use of the national menuCH survey data, with its rigorous two-day 24-hour recall methodology and comprehensive adjustment for confounders, provides a robust dataset for analysis. The findings, highlighting that even non-SSB consumers in Switzerland have only moderate diet quality, offer significant implications for public health strategies, suggesting that a singular focus on SSB reduction may be insufficient for overall health promotion.

Introduction:

1. The study utilizes data from the menuCH survey conducted in 2014–2015. Given that the current date is 2026, this data is over a decade old. Please explicitly address the potential "age" of the data in the Introduction or early in the Methods. Are there reasons to believe that Swiss dietary habits have remained stable enough over the last 10–12 years for these findings to be currently relevant? Have there been major policy changes (e.g., sugar taxes, front-of-pack labeling) in Switzerland since 2015 that might have altered this landscape?
2. The introduction outlines the aim well but lacks a specific hypothesis regarding the direction of the association based on European cultural contexts. It would be beneficial to briefly mention whether you hypothesized a "substitution effect" (where SSB consumers might compensate by eating healthier food) or a "clustering effect" (where unhealthy behaviors cluster together) specifically within the Swiss context, to frame the results more effectively.

Materials and Methods

1. "non-consumers" are defined as those consuming <1% of total daily energy from SSB (Line 113). Please clarify the rationale for the <1% cutoff rather than 0%. Is this to account for measurement error or trace ingredients? If a participant drank one sip of juice, are they a "non-consumer"? A brief explanation of why strict 0g intake was not used would clarify the grouping.
2. Line 115: You utilized the AHEI-2010. Given the publication year (2026), please briefly justify why the AHEI-2010 was chosen over potentially newer indices (e.g., AHEI-2019/2020 or specific European diet quality scores). Discuss if the AHEI, which is heavily validated in US cohorts, is fully translatable to the Swiss diet without modification (beyond removing the SSB component).

Results

1. Line 200: The text states, "No clear differences between components of the non-SSB AHEI... were observed". This is puzzling. If the total score differs significantly, some components must be driving this difference. Is it that no single component was significant, but the sum was? It would be very helpful to show a heatmap or a more detailed breakdown of which specific food groups (e.g., vegetables, whole grains) were lower in the High-SSB group to guide public health interventions.
2. Line 239: In the Italian-speaking region, High-SSB consumers appeared to have higher scores than Low-SSB consumers. The High-SSB sample size in the Italian region is likely very small (n=15 based on Table 1). Please explicitly flag this in the Results section as potentially being a statistical artifact due to the small sample size, rather than a robust cultural finding, to prevent misinterpretation.

Discussion

1. The geometric means for all groups are low (34–41 points out of 100). Please expand the discussion on why Swiss adults score so low on the US-based AHEI. Is the Swiss diet objectively poor, or does the AHEI penalize common Swiss dietary habits (e.g., high consumption of dairy/cheese, which might be rated differently in AHEI)? A short paragraph on the cross-cultural validity of the scoring system here is warranted.
2. Line 210, Line 221: The discussion heavily compares findings to US studies. Are there really no comparable European studies? Even if they used different indices (like the Mediterranean Diet Score), comparing the patterns of SSB intake and diet quality with French, German, or Italian data would be more relevant than US comparisons, given the different food environments.
3. Line 291: The conclusion suggests "alternative food choices" should be investigated. Be more prescriptive based on your data. Since you know which non-SSB components were measured, you can suggest specifically: "Interventions should not only tax sugar but explicitly subsidize [Vegetables/Whole Grains], as these were the specific deficits observed in SSB consumers."

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

This paper addresses an important research objective by evaluating diet quality using clusters of sweetened beverage consumers. The authors make good use of an existing survey and provide policy relevant evidence for the country under study, which can help inform decision making and support dietary recommendations aimed at reducing sugar intake.

The authors have successfully addressed all comments from the previous review. I would recommend one additional English language edit to further improve clarity and flow.

Reviewer 4 Report

Comments and Suggestions for Authors

The modifications are very good, and I think the article is acceptable.