Cooking Skills and Mediterranean Diet Adherence: Societal Insights from the iMC SALT Trial

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Overall, the article is well structured, methods are clearly described and are appropriate to testing the hypothesis, and the logic is well-connected. It is appropriate for the scope of the journal. The methods are mostly sufficiently described for replicability; see below for how this can be strengthened. Strong description of the NOVA groups. The tables/diagrammed are well constructed and the choice to include them was sound. The use of color is especially helpful in making detail clear and easier to understand. Ethics and Statistical Analysis are concisely but clearly described. The Data Availability section would be clearer if "reasonable request" were more clearly defined, but this may be a standard for this journal. The references are chosen well and concisely yet clearly integrated into the paper (with the exception of points noted below). Although many are older articles, a solid representation of recent articles is included and the older articles are used appropriates to give history and context. The gap in knowledge is identified; this identification could be made stronger; see below. The conclusions are consistent with the evidence and arguments; see below for how the discussion and conclusion can be strengthened and can underscore how the study applies this data and newer theories to a long-standing problem. Revisions are recommended, though these are relatively minimal:

Include in the abstract the fact that this study was conducted in Portugal. This is implied in the Introduction, but it was not until the Methods section that this is directly stated. This would be helpful to other researchers who are reading abstracts to "sort" potential articles for use. 

Proofread for grammar/punctuation, flow, and sentence structure. In places, the clarity of a point is lost or confused or the apparent points within a sentence contradict each other, e.g., the Mediterranean diet is not "characterized by high consumption...of healthy fats" though it does emphasize healthy fats. The sentence structure results in the appearance of error. Other examples of when structure interferes with clarity:

     line 133 "Red meats and processed meats considered detrimental components..." sounds like the foods are thinking; improved punctuation would solve this; the same is true for lines 342 and 354.

     In lines 341-2, your sentence structure/wording indicates that you are saying that "adults with poor cooking skills were less likely to have...obesity compared to [those with] advanced cooking skills...." Is this what you intend to say?

     The missing word "the" on line 340 does not greatly interfere with meaning, but I recommend running a grammarchecker.

Avoid the word "issues," as in places it confuses your point, e.g., line 45. 

Clarify "worse diet adequacies" (line 49).

Clarify "in resisting unhealthy food environments" (lines 58-9) - this is an important set of concepts in PH nutrition that some readers may not understand.

Consider including the concept of "self-efficacy" rather than relying only on "confidence." The two concepts are not identical and the former is central to PH interventions (especially education-related ones). It would also integrate more theory into the paper.

Lines 86-87: Were these the only faculty that promoted the study? For example, were professors in other departments also promoting it? In other words, were these the only faculty excluded from participation? If yes to both, say so more directly rather than relying on readers to figure it out from your use of i.e., (Clarity)

Was not including salt in cooking a self-report? If so, was it through their health checkup or a screening questionnaire? How did you obtain access to the health information in lines 84-7? For example, did participants directly give you their health exam results or did they sign a permission form for the medical team to release them? Was willingness to grant permission for release of this information (or give it directly) an inclusion / exclusion criterion?

It would be helpful for readers to have comparison data for the national level Cooking Skills Scale in order to compare the relative skills of the study population to the general population. 

Why is "Juliana soup" specifically included as a proxy for calculating the vegetable score? What is this soup?

Consider adding the specific questions used to assess confidence (again, consider using self-efficacy as a construct and potentially revising the scale to include this in future studies), enjoyment, and motivation to start learning how to cook (?vs. improving skills?), lines 102-104 to more fully describe the scale, especially sine you provide detail on the CSS.

Were the M/F differences in Figure 1 statistically significant?

Recommend a sentence or two be added to explain what Culinary Medicine is, rather than simply providing a reference. This is not only an important emerging approach to health (and one that is supported through state and private insurance or through supplemental food provision programs in some areas), but also is an approach that some readers might be completely unfamiliar with. 

Consider moving the points made in the paragraph on long-term benefits of developing cooking skills (lines 376-381) to the introduction, as the context provided by these points may be helpful to some readers. 

Finally, the recommendations made in the paper are sound, but perhaps somewhat generic. More specifically actionable recommendations would strengthen the paper. For example, how could skills be taught - and when and where? Should school curricula be enhanced? Should individuals who are pregnant have access to specific classes? (Might hospitals or pregnancy/birth support programs make workshops available?) Are there ways for community health workers to be trained and to be involved in teaching these skills in their communities and places of employment? Are there community or individual spaces specific to Portugal that would be ideal locations for such classes? Are there any policies that should be changed, created, or better supported? Including more specifics is likely to "bring more eyes" to your paper and make it more useful to the fields it addresses. It also will help the article further stand apart from others on the topics of obesity and the MD by underscoring the importance of considering skills and implementing interventions to improve them.

Author Response

Reviewer: Overall, the article is well structured, methods are clearly described and are appropriate to testing the hypothesis, and the logic is well-connected. It is appropriate for the scope of the journal. The methods are mostly sufficiently described for replicability; see below for how this can be strengthened. Strong description of the NOVA groups. The tables/diagrammed are well constructed and the choice to include them was sound. The use of color is especially helpful in making detail clear and easier to understand. Ethics and Statistical Analysis are concisely but clearly described. The Data Availability section would be clearer if "reasonable request" were more clearly defined, but this may be a standard for this journal. The references are chosen well and concisely yet clearly integrated into the paper (with the exception of points noted below). Although many are older articles, a solid representation of recent articles is included and the older articles are used appropriates to give history and context. The gap in knowledge is identified; this identification could be made stronger; see below. The conclusions are consistent with the evidence and arguments; see below for how the discussion and conclusion can be strengthened and can underscore how the study applies this data and newer theories to a long-standing problem. Revisions are recommended, though these are relatively minimal:

Include in the abstract the fact that this study was conducted in Portugal. This is implied in the Introduction, but it was not until the Methods section that this is directly stated. This would be helpful to other researchers who are reading abstracts to "sort" potential articles for use.

Author’s Response: Thank you for your thorough and constructive feedback. We appreciate your positive evaluation of the article’s structure, clarity, and relevance to the journal's scope. In response to your recommendation, we have revised the abstract to explicitly state that the study was conducted in Portugal. This clarification will help readers more easily contextualize the findings during abstract-based searches and sorting. We hope this change enhances the accessibility and usefulness of our study for the research community.

 

Reviewer: Proofread for grammar/punctuation, flow, and sentence structure. In places, the clarity of a point is lost or confused or the apparent points within a sentence contradict each other, e.g., the Mediterranean diet is not "characterized by high consumption...of healthy fats" though it does emphasize healthy fats. The sentence structure results in the appearance of error. Other examples of when structure interferes with clarity:

Line 133 "Red meats and processed meats considered detrimental components..." sounds like the foods are thinking; improved punctuation would solve this; the same is true for lines 342 and 354.

In lines 341-2, your sentence structure/wording indicates that you are saying that "adults with poor cooking skills were less likely to have...obesity compared to [those with] advanced cooking skills...." Is this what you intend to say?

The missing word "the" on line 340 does not greatly interfere with meaning, but I recommend running a grammarchecker.

Avoid the word "issues," as in places it confuses your point, e.g., line 45.

Clarify "worse diet adequacies" (line 49).

Clarify "in resisting unhealthy food environments" (lines 58-9) - this is an important set of concepts in PH nutrition that some readers may not understand.

Author’s response: Thank you for your detailed and insightful suggestions regarding grammar, sentence structure, and clarity. We have conducted a thorough proofreading of the manuscript, with particular attention to sentence flow, punctuation, and the elimination of any structural ambiguities.

• The sentence referencing the Mediterranean diet has been reworded to accurately reflect that the diet emphasizes healthy fats rather than being characterized by high consumption of them.
• We corrected the sentence on line 133 for punctuation to avoid anthropomorphism and ensure clarity ("Red meats and processed meats, considered detrimental components...").
• Similar structural corrections have been made to lines 342 and 354.
• Regarding lines 341–342, we appreciate your observation. The original sentence unintentionally suggested the opposite of our intended meaning. We have revised it to clearly convey that adults with poor cooking skills were more likely to have obesity compared to those with advanced skills.
• The missing article on line 340 has been inserted, and we have run a grammar and clarity check throughout the manuscript.
• We have replaced vague terms such as “issues” (e.g., line 45) with more precise language, and clarified expressions such as “worse diet adequacies” and “in resisting unhealthy food environments,” ensuring they are accessible to readers less familiar with public health nutrition terminology.

We are grateful for your careful reading and valuable recommendations, which have substantially improved the clarity and quality of the manuscript.

 

Reviewer: Consider including the concept of "self-efficacy" rather than relying only on "confidence." The two concepts are not identical and the former is central to PH interventions (especially education-related ones). It would also integrate more theory into the paper.

Author’s response: Thank you for this insightful suggestion. We agree that the concept of self-efficacy offers a more theoretically grounded and precise framework than confidence, particularly within the context of public health and education-based interventions. In response, we have revised relevant sections of the manuscript to incorporate the concept of self-efficacy, clarifying its role in influencing culinary behaviors and dietary choices. This addition also strengthens the theoretical foundation of the paper by aligning our discussion more closely with established behavioral change models in public health nutrition.

 

Reviewer: Lines 86-87: Were these the only faculty that promoted the study? For example, were professors in other departments also promoting it? In other words, were these the only faculty excluded from participation? If yes to both, say so more directly rather than relying on readers to figure it out from your use of i.e., (Clarity)

Author’s comment: Thank you for pointing out the need for greater clarity. To address this, we have revised the sentence to explicitly state that only faculty members from the Faculty of Nutrition and Food Sciences promoted the study and were therefore excluded from participation. No other faculty were involved in the promotion or excluded. This clarification ensures that readers do not need to infer this information from the original phrasing.

 

Reviewer: Was not including salt in cooking a self-report? If so, was it through their health checkup or a screening questionnaire? How did you obtain access to the health information in lines 84-7? For example, did participants directly give you their health exam results or did they sign a permission form for the medical team to release them? Was willingness to grant permission for release of this information (or give it directly) an inclusion / exclusion criterion?

Author’s Response: Thank you for the opportunity to clarify this issue. As described in the study protocol (doi: 10.1136/bmjopen-2019-035898), the study was approved by the Ethics Committee of the Hospital Center. After the participants agreed to participate in the study, the physician applied a form to the participants recording whether or not they met the inclusion/exclusion criteria by self-report.

 

Reviewer: It would be helpful for readers to have comparison data for the national level Cooking Skills Scale in order to compare the relative skills of the study population to the general population.

Author’s Response: To the best of the authors' knowledge, there is no study with data evaluating the population's culinary skills. Studies that were found with the Portuguese population were included in the discussion of this work.

 

Reviewer: Why is "Juliana soup" specifically included as a proxy for calculating the vegetable score? What is this soup?

Author’s Response: Thank you for your question regarding the inclusion of "Juliana soup". Juliana soup is a very typical and staple type of soup in Portugal, widely consumed across different settings. In many Portuguese restaurants, when the menu simply lists "soup" without further specification, it often refers to this particular vegetable-based soup. Because of its prevalence and consistent vegetable content, we included Juliana soup as a proxy for calculating the vegetable content in soups to better reflect common dietary patterns in the Portuguese population.

 

Reviewer: Consider adding the specific questions used to assess confidence (again, consider using self-efficacy as a construct and potentially revising the scale to include this in future studies), enjoyment, and motivation to start learning how to cook (?vs. improving skills?), lines 102-104 to more fully describe the scale, especially sine you provide detail on the CSS.

Author’s Response: Thank you for your valuable suggestion. We have expanded the description of the scales used to assess confidence, enjoyment, and motivation to provide greater clarity. We also acknowledge the distinction between confidence and self-efficacy and recognize that self-efficacy is a more theoretically grounded construct for future studies. While our current study used confidence-related questions as a proxy, we plan to incorporate validated self-efficacy measures and consider distinguishing between motivation to start learning versus improving skills in subsequent research.

 

Reviewer: Were the M/F differences in Figure 1 statistically significant?

Author’s Response: The differences were not statistically significant. We add this information on the text.

 

Reviewer: Recommend a sentence or two be added to explain what Culinary Medicine is, rather than simply providing a reference. This is not only an important emerging approach to health (and one that is supported through state and private insurance or through supplemental food provision programs in some areas), but also is an approach that some readers might be completely unfamiliar with.

Author’s Response: Thank you for the comment. The explanation about what Culinary Medicine is was added.

 

Reviewer: Consider moving the points made in the paragraph on long-term benefits of developing cooking skills (lines 376-381) to the introduction, as the context provided by these points may be helpful to some readers.

Author’s Response: Thank you for the suggestion regarding the placement of the paragraph on the long-term benefits of developing cooking skills. While we agree that these points provide important context, we believe their placement in the Discussion section is more appropriate, as it allows us to directly relate these benefits to our study’s findings and interpret the results within that framework. Moving the paragraph to the Introduction might disrupt the logical flow and reduce the impact of the discussion. We appreciate your understanding of this decision.

 

Reviewer: Finally, the recommendations made in the paper are sound, but perhaps somewhat generic. More specifically actionable recommendations would strengthen the paper. For example, how could skills be taught - and when and where? Should school curricula be enhanced? Should individuals who are pregnant have access to specific classes? (Might hospitals or pregnancy/birth support programs make workshops available?) Are there ways for community health workers to be trained and to be involved in teaching these skills in their communities and places of employment? Are there community or individual spaces specific to Portugal that would be ideal locations for such classes? Are there any policies that should be changed, created, or better supported? Including more specifics is likely to "bring more eyes" to your paper and make it more useful to the fields it addresses. It also will help the article further stand apart from others on the topics of obesity and the MD by underscoring the importance of considering skills and implementing interventions to improve them.

Author’s response: Thank you for your insightful suggestions regarding the specificity of our recommendations. We agree that more actionable and context-specific guidance would enhance the practical impact of our paper. In the revised manuscript, we have expanded the recommendations to include targeted strategies such as integrating culinary skills education into school curricula, especially at early ages, and offering tailored cooking workshops for pregnant individuals through hospitals and prenatal support programs. We also discuss the potential role of community health workers in delivering cooking skill interventions within local communities and workplaces. Additionally, we highlight specific community centers and cultural hubs in Portugal that could serve as ideal venues for these programs, as well as policy measures that could support the broader implementation of culinary education, including incentives for health institutions to incorporate cooking classes into preventive care. These more detailed and contextually grounded recommendations aim to increase the relevance and appeal of our work to practitioners and policymakers focused on obesity prevention and the Mediterranean diet.

Reviewer 2 Report

Comments and Suggestions for Authors

Check in text citations.

Author Response

Thank you.

Reviewer 3 Report

Comments and Suggestions for Authors

Overall, interesting data and conclusions. There are several places in the results section, where the data could be reported more clearly and specifically. You give the mean age of the women participants in parantheses but not the mean age of the men in the first sentence. It would also be helpful to include whether the lower intake of sodium and potassium and lower sodium to potassium ration observed in women was significant.  In the discussion section, the finding of higher energy intakes in those with better culinary skills and adherence to the Mediterranean Diet would benefit from more discussion. Since unhealthy diets with more processed foods are usually associated with excessive energy intake and obesity it would be helpful to explain this more. For example were overall energy intakes in both groups within normal ranges? How did BMI relate to energy intake between the groups. Because obesity is part of the constellation of NCD, it would be good to discuss this more.

Author Response

Reviewer: Overall, interesting data and conclusions. There are several places in the results section, where the data could be reported more clearly and specifically. You give the mean age of the women participants in parantheses but not the mean age of the men in the first sentence.

Author’s comment: Thank you for the opportunity to clarify that the value in parentheses is the average age of the group of 111 participants, as can be seen in Table 1.

 

Reviewer: It would also be helpful to include whether the lower intake of sodium and potassium and lower sodium to potassium ration observed in women was significant. 

Author’s comment: Thank you for your observation. While energy intake was not significantly lower in women compared to men, the significantly lower sodium and potassium intake and sodium-to-potassium ratio observed in women may be attributed to differences in dietary patterns and food choices rather than total energy consumption. Women could tend to consume foods with lower sodium content or different seasoning preferences, which has been noted in previous studies. Additionally, physiological differences and varying nutrient requirements between sexes could contribute to these intake differences. We have included this discussion in the revised manuscript to better contextualize our findings.

 

Reviewer: In the discussion section, the finding of higher energy intakes in those with better culinary skills and adherence to the Mediterranean Diet would benefit from more discussion. Since unhealthy diets with more processed foods are usually associated with excessive energy intake and obesity it would be helpful to explain this more. For example were overall energy intakes in both groups within normal ranges? How did BMI relate to energy intake between the groups. Because obesity is part of the constellation of NCD, it would be good to discuss this more.

Author’s comment: Thank you for your valuable suggestion to expand the discussion on the finding of higher energy intakes among individuals with better culinary skills and greater adherence to the Mediterranean Diet. While these individuals showed higher energy intake, it is important to clarify that overall energy intake in the sample remained within typical ranges. Notably, women had significantly lower energy intake and BMI compared to men, yet demonstrated significantly higher culinary skills and Mediterranean Diet adherence scores.

The higher energy intake observed in those with better culinary skills may reflect increased food preparation and consumption of more nutrient-dense, whole foods typical of the Mediterranean Diet, which can be more energy-rich but healthier than highly processed foods. This contrasts with unhealthy dietary patterns characterized by processed food consumption, which often leads to excessive energy intake without nutritional benefits and contributes to obesity.

Both men and women in our study were classified as overweight (BMI 25–29.9), but the lower BMI among women, alongside their higher culinary skills and diet adherence, suggests that cooking competence and diet quality may help moderate weight status despite variations in energy intake. These findings underscore the complex interplay between diet quality, energy intake, cooking skills, and obesity risk. We have expanded the discussion in the manuscript to better highlight these nuances, emphasizing the importance of focusing on culinary skills and dietary patterns as key factors in improving nutritional status and addressing non-communicable diseases.