The Carbon Footprint of School Lunch: Moving Toward a Healthy and Sustainable Future for the Next Generation

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

I disagree with the basic premise of carbon emissions from animal products. This is theoretical and has no scientific basis. The authors should consider much more relevant issues such as transportation that uses fossil fuels and other sources of industrial pollution. As for children's health, as a pediatric nutritionist, I affirm that a plant-based diet is very healthy and should be encouraged, but without giving up animal food sources, which contain essential nutrients. Dairy products are a fundamental source of calcium, which is essential for children's growth, and a plant-based diet can never be sufficient due to its lower bioavailability. This also applies to iron, which, in addition to ensuring that anemia does not occur, is a fundamental source for neurocognitive development. Thus, the study is interesting, but unacceptable because it is based on mistaken premises.

Author Response

Reviewer 1

Comment 1:

I disagree with the basic premise of carbon emissions from animal products. This is theoretical and has no scientific basis. The authors should consider much more relevant issues such as transportation that uses fossil fuels and other sources of industrial pollution. As for children's health, as a pediatric nutritionist, I affirm that a plant-based diet is very healthy and should be encouraged, but without giving up animal food sources, which contain essential nutrients. Dairy products are a fundamental source of calcium, which is essential for children's growth, and a plant-based diet can never be sufficient due to its lower bioavailability. This also applies to iron, which, in addition to ensuring that anemia does not occur, is a fundamental source for neurocognitive development. Thus, the study is interesting, but unacceptable because it is based on mistaken premises.

Response 1:

 

Thank you for your review and comments. We appreciate the opportunity to clarify and strengthen the points presented in our paper regarding the environmental impact of animal products and the feasibility of achieving nutritional adequacy with reduced reliance on these sources.

There is much scientific evidence that the food system contributes one-third or more of total anthropogenic greenhouse gas emissions (GHGE) (Crippa et al. 2021, Tubiello et al. 2021), including that animal-source foods are responsible for over 50% of these (Xu et al. 2021). It has been shown by a number of modeling studies that reducing GHGE from all major emission sources in addition to food system, including transportation, energy generation, and cement production, is needed to increase the probability of keeping total emissions under a level that would be catastrophic for humans and most other life forms (Bajželj et al. 2014, Clark et al. 2020). We have added some text in the introduction with more details documenting the critical role of plant-based diets in mitigating climate change (citing only existing references in the ms).

Bajželj, B., Richards, K.S., Allwood, J.M., Smith, P., Dennis, J.S., Curmi, E., and Gilligan, C.A. 2014. Importance of food-demand management for climate mitigation. Nature Climate Change 4(10):924-929. DOI: 10.1038/nclimate2353.

Clark, M.A., Domingo, N.G.G., Colgan, K., Thakrar, S.K., Tilman, D., Lynch, J., . . . Hill, J.D. 2020. Global food system emissions could preclude achieving the 1.5° and 2°C climate change targets. Science 370(6517):705-708. DOI: 10.1126/science.aba7357.

Crippa, M., Solazzo, E., Guizzardi, D., Monforti-Ferrario, F., Tubiello, F.N., and Leip, A. 2021. Food systems are responsible for a third of global anthropogenic GHG emissions. Nature Food 10.1038/s43016-021-00225-9.

Tubiello, F.N., Rosenzweig, C., Conchedda, G., Karl, K., Gütschow, J., Xueyao, P., . . . Sandalow, D. 2021. Greenhouse gas emissions from food systems: building the evidence base. Environmental Research Letters 16(6):065007. DOI: 10.1088/1748-9326/ac018e.

Xu, X., Sharma, P., Shu, S., Lin, T.-S., Ciais, P., Tubiello, F.N., . . . Jain, A.K. 2021. Global greenhouse gas emissions from animal-based foods are twice those of plant-based foods. Nature Food 2(9):724-732. DOI: 10.1038/s43016-021-00358-x.

 

We recognize the importance of considering multiple pollution sources within the food system, including transportation. Transportation-driven emissions from low-emissions foods, such as vegetables and fruits, do play a role in the overall climate footprint of those foods. However, when it comes to the most climate-intensive foods, such as beef, transportation or “food miles” play a demonstrably small role in its climate footprint in comparison to other sources of emissions, such as land-use conversion. When land-use impacts of beef production are included in assessments, the greenhouse gas emissions impacts of meat consumption in the average American diet come close to per capita emissions from U.S. fossil fuel production. According to the Environmental Protection Agency’s most recent greenhouse gas inventory, cattle alone are one of the top sources of domestic emissions, nearly equivalent to the energy sector and surpassing transportation. 

In addition, Sandström et al. provide an insightful analysis of the greenhouse gas footprints of EU diets, demonstrating that while food transport contributes to emissions, it accounts for only about 6% of the total emissions from the food system​. In contrast, the production of dairy, meat, and eggs contributes significantly more, amounting to 83% of the emissions within the food sector. This suggests a substantial potential for mitigation through dietary adjustments (Sandström et al, 2018).

One of the key opportunities for emissions drawdown as identified by the Intergovernmental Panel on Climate Change (IPCC) is dietary shifts toward more plant-based consumption. Plant-based foods have a dramatically lower climate footprint than animal-based foods. Half of all food-related emissions come from meat and dairy products, which are responsible for at least 16% of global greenhouse gases. It is well-established that plant-based food shifts can address the significant environmental impact of food production while establishing healthy diets, improving food security and climate resiliency, while stemming the tide of biodiversity loss, as noted in the U.N.’s paper on sustainable diets for healthy people and a healthy planet. Regarding nutritional adequacy, it is well-documented that diverse, plant-based diets can meet dietary needs across all age groups and offer health benefits. For instance, the Academy of Nutrition and Dietetics highlights that vegetarian and vegan diets can fully support healthy living in people of all ages, provided they are well-structured and consider key nutrients  (Melina et al. 2016). The Dietary Guidelines Scientific Advisory Committee, a body that provides independent science-based advice to the U.S. Department of Health and Human Services and the U.S. Department of Agriculture, just released a report to guide the development of the  2025-2030 Dietary Guidelines for Americans, prioritized plant-based protein sources, such as beans, peas, and lentils, recommending they be moved above the animal protein in the protein category, while also recommending reducing red and processed meat consumption and de-prioritizing meat, poultry and eggs. 

Meanwhile, the Dietary Guidelines for Americans continue to emphasize fiber-rich diets, which animal products do not provide, and which most Americans do not consume in adequate amounts according to these recommendations. Meat, dairy, and eggs tend to be higher in saturated fat, cholesterol, and sodium and are linked with chronic diseases like cardiovascular disease, cancer, and diabetes. Diets rich in plants are nutrient and fiber-dense and associated with lower mortality. The 2015-2020 dietary guidelines recommended less meat, especially for teenage boys, and that all children increase their consumption of vegetables and plant-based proteins. 

New nutrition standards released in 2024 by the USDA for its childhood nutrition programs (including the National School Lunch Program, which serves millions of public-school children) emphasize entrees with beans, peas, and lentils, for many of these reasons, while attempting to make it easier for children to access fortified plant-based milk alternatives, given the substantial amount of lactose-intolerant children, particularly in nonwhite communities. Leading health organizations including the American Medical Association, the American Cancer Society, and the Harvard T.H. Chan School of Public Health, recommends reducing red and processed meats. 

Our analysis highlights the significant benefits of dietary shifts toward more plant-based patterns, which not only reduce environmental impacts but also promote public health. We advocate for an approach to dietary recommendations that takes these benefits into account and aligns with health and sustainability goals.

Reviewer 2 Report

Comments and Suggestions for Authors

As we are witnessing the consequences of global warming today, it is the duty of all people, especially the academic and research community, to help mitigate the negative consequences. It should not be overlooked that the production, processing and consumption of food also leaves an imprint on our planet.

It is commendable that the authors have focussed this issue on the most vulnerable population group - school children, who at this age are developing an awareness of the impact of human activity on the environment and the need to mitigate this negative impact. In addition, this group is particularly vulnerable because they are at risk of obesity, which could be handled by school meals as a public health tool.

The goal of this study was to quantify the carbon footprint of primary schools lunch menus in six large urban school districts in the United States and to simulate the impact of sustainable food policies on reducing carbon emissions while ensuring that nutritional needs remain adequate.

I believe that the work is of satisfactory quality and that it will help to advance scientific knowledge both on the topic of the impact of diet on the carbon footprint and on the adoption of proposals for new sustainable policies related to school lunches.

Before publication, I suggest making the following changes:

- The paper lacks a statistical analysis. I request that a statistical analysis is carried out and the methods used are described. It must be shown whether there are statistically significant differences between the meals and between the changes made, both in terms of nutritional value and carbon footprint. The aim of the statistical analysis must be to show the impact of the modification and its strength, taking into account the potential risks of losing the nutritional balance of the meal for this highly sensitive population. After conducting the statistical analysis, it is necessary to revise the presentation of all results and conclusions and include the statistical significance data in the abstract.

- Please indicate in the methodology the number of meals analysed in each district. It is desirable that in all presentations (tables and figures) the number (n=...) is indicated next to the meal.

I recommend that authors remove Figure 2 as it shows the same results as Table 1.

- Figures 3a-f: Please remove the title within the figure as the captions are informative enough. Please also remove the sentences referring to total CO2 emissions as this is not evident from the figure but can be read from Figure 4a. It is not necessary to repeat data.

- Figure 6: Please add a title for the x-axis to all figures and add an additional figure on calorie content. Add a label to each graph, e.g. a - f.

- Supplementary material: In the "LCA conversion table", the unit of measurement gCO2eq/g food should be indicated.

- As it was found that there is scope for optimising nutritional values and harmonising with the recommendations for all meals analysed (including the "no strategy" option), it would be desirable if the carbon footprint of meals in all districts were also presented in terms of g CO2 eq/kcal. Such a presentation would allow conclusions to be drawn about the balance of nutrient density, energy density and carbon footprint, which is a prerequisite for the full sustainability of school catering.

Author Response

Reviewer 2:

Comment 1:

As we are witnessing the consequences of global warming today, it is the duty of all people, especially the academic and research community, to help mitigate the negative consequences. It should not be overlooked that the production, processing, and consumption of food also leaves an imprint on our planet.

It is commendable that the authors have focussed this issue on the most vulnerable population group - school children, who at this age are developing an awareness of the impact of human activity on the environment and the need to mitigate this negative impact. In addition, this group is particularly vulnerable because they are at risk of obesity, which could be handled by school meals as a public health tool.

The goal of this study was to quantify the carbon footprint of primary schools lunch menus in six large urban school districts in the United States and to simulate the impact of sustainable food policies on reducing carbon emissions while ensuring that nutritional needs remain adequate.

I believe that the work is of satisfactory quality and that it will help to advance scientific knowledge both on the topic of the impact of diet on the carbon footprint and on the adoption of proposals for new sustainable policies related to school lunches.

Before publication, I suggest making the following changes:

- The paper lacks a statistical analysis. I request that a statistical analysis is carried out and the methods used are described. It must be shown whether there are statistically significant differences between the meals and between the changes made, both in terms of nutritional value and carbon footprint. The aim of the statistical analysis must be to show the impact of the modification and its strength, taking into account the potential risks of losing the nutritional balance of the meal for this highly sensitive population. After conducting the statistical analysis, it is necessary to revise the presentation of all results and conclusions and include the statistical significance data in the abstract.

Response 1:

For our primary objective, our LCA calculations applied the best available data to calculate the actual carbon footprint of specific known meals, not of meals sampled from a larger population of meals of a certain type.  We  grouped the various types of meals (vegan, vegetarian, poultry, beef) into categories and considered the recipes we have to be representative of a larger population of meals of each type. We then conducted t-tests to look for differences. We have added the following text to the paper:

The average for each meal group across all districts is also given (Table 1).  Beef meal carbon footprints were statistically significantly (p<0.0001) higher than all other meal types.  Plant-based meals were statistically significantly lower than all other meal types (p=0.0011 for vegetarian, p<0.0001 for chicken, p=0.0003 for fish, and p<0.0001 for pork.)

 

Comment 2:

- Please indicate in the methodology the number of meals analysed in each district. It is desirable that in all presentations (tables and figures) the number (n=...) is indicated next to the meal.

Response 2:

This is a good suggestion.  The numbers of meals of each category are now given in Table 1.

Comment 3:

I recommend that authors remove Figure 2 as it shows the same results as Table 1.

Response 3:

Thank you for your suggestion to reconsider the inclusion of Figure 2. We have removed Figure 2 from the manuscript as advised. 

Comment 4:

- Figures 3a-f: Please remove the title within the figure as the captions are informative enough. Please also remove the sentences referring to total CO2 emissions as this is not evident from the figure but can be read from Figure 4a. It is not necessary to repeat data.

Response 4:

Thank you for your suggestion to remove titles within the figures. While we agree that it is somewhat redundant, we would like to leave them in place as it helps the reader quickly identify the content of the figure at a glance without needing to refer back to the caption. We have removed the sentences referring to total CO2 emissions as requested.  If this is really important for the review process, we are happy to remove the titles.

Comment 5:

- Figure 6: Please add a title for the x-axis to all figures and add an additional figure on calorie content. Add a label to each graph, e.g. a - f.

Response 5:

We have ensured that the x-axis titles and graph labels have been updated in Figure 6 to enhance clarity and readability, as you suggested.

Thank you for your suggestion to add a figure illustrating calorie content. We would like to note that all meal comparisons in our study were designed to be isocaloric, ensuring that each meal provides an equivalent amount of calories. This design choice was intended to isolate the impact of food composition on environmental outcomes, without the confounding variable of differing caloric intake.

Given that the calorie content across meals is consistent, we believe that adding a figure to display this would not contribute additional insights into our analysis. We appreciate your feedback and hope this explanation clarifies why we opted not to include a separate figure for calorie content. If the addition of such a figure is still deemed necessary, we are open to further discussion on how best to integrate this into our presentation.

Comment 6:

- Supplementary material: In the "LCA conversion table", the unit of measurement gCO2eq/g food should be indicated.

Response 6:

Thank you for highlighting the need to clarify the unit of measurement in the "LCA conversion table" within our supplementary material. We have updated the table to ensure that the unit of measurement is clearly indicated as gCO2eq/g food.

We appreciate your attention to detail and your assistance in improving the comprehensiveness of our documentation.

Comment 7:

As it was found that there is scope for optimising nutritional values and harmonising with the recommendations for all meals analysed (including the "no strategy" option), it would be desirable if the carbon footprint of meals in all districts were also presented in terms of g CO2 eq/kcal. Such a presentation would allow conclusions to be drawn about the balance of nutrient density, energy density and carbon footprint, which is a prerequisite for the full sustainability of school catering.

Response 7:

 

The various lunches were designed to meet a narrow range in kcals, so showing gCO2eq/kcal will have a similar trend to gCO2eq kcal/meal.

 

Reviewer 3 Report

Comments and Suggestions for Authors

This paper, titled The Carbon Footprint of School Lunch: Moving Toward a Healthy and Sustainable Future for the Next Generation, aims to quantify the carbon footprint of elementary school lunch menus across six major urban school districts in the United States. The study estimates the reduction in carbon emissions resulting from changes in these school lunch programs while exploring the nutritional implications (e.g., protein, fiber, vitamin A, vitamin C, calcium, and iron) for one school district and discussing their impact on student health in the US.

 

Materials and Methods:

The authors chose six school districts located in major urban areas and analyzed a total of twenty distinct meals per district. However, I believe the sample size is small and potentially biased. There should be further explanation regarding the selection criteria, such as the size of the schools, the number of students, and the income levels of the families. Why were these specific schools selected? Addressing these points would strengthen the methodology.

Additionally, the title of Table 1 should be corrected for clarity: Table 1. g CO2eq Emissions Across Meal Types Within Each District Used for Policy Modeling. Values Are Shaded When Recipes Were Imputed From Other Districts.

 

In discussion: The paper lacks a clear calculation of the economic costs associated with these scenarios. It would also be valuable to explore how the proposed changes could impact children's health and promote healthy eating habits. The authors should include an analysis of the economic feasibility of the recommended products and their availability in school districts. Furthermore, it is essential to address the expected acceptance of these dietary changes and student behaviors toward the proposed meal scenarios.

 

In conclusions, In Line 507, the authors discuss a food waste reduction strategy. It would be helpful to highlight the economic significance of reducing food waste as part of the conclusions. This addition would provide a more comprehensive perspective on the potential benefits of the proposed changes.

 

Author Response

Reviewer 3

Comment 1:

This paper, titled The Carbon Footprint of School Lunch: Moving Toward a Healthy and Sustainable Future for the Next Generation, aims to quantify the carbon footprint of elementary school lunch menus across six major urban school districts in the United States. The study estimates the reduction in carbon emissions resulting from changes in these school lunch programs while exploring the nutritional implications (e.g., protein, fiber, vitamin A, vitamin C, calcium, and iron) for one school district and discussing their impact on student health in the US.

Materials and Methods:

The authors chose six school districts located in major urban areas and analyzed a total of twenty distinct meals per district. However, I believe the sample size is small and potentially biased. There should be further explanation regarding the selection criteria, such as the size of the schools, the number of students, and the income levels of the families. Why were these specific schools selected? Addressing these points would strengthen the methodology.

Response 1:

Thank you for your thoughtful feedback. We chose one school in each of the 6 regions (as illustrated in Figure 1) where the menus were readily accessible.  Figure 1 does provide the racial demographics and size of the districts.  We agree with the reviewer that the paper should calculate significantly large districts so that it’s not thrown off by one small district; therefore, each district we chose in the 6 regions was large.  Chicago, New York, and Miami  are very large districts, with 322,106, 1,058,888, and 333,955 students, respectively. The other three are also much greater than the average school district size in the U.S. of approximately 3,700, with Austin, Long Beach, and Portland serving 74,871, 67,573, 45,456, respectively.  We would like to clarify that this paper is intended as a policy paper rather than a large-scale statistical analysis. Its primary aim is to explore potential impacts, propose actionable recommendations, and provide a practical framework for implementation. While the sample selection may not fully represent all possible scenarios, it serves as an illustrative example to support the policy argument rather than functioning as a definitive or scalable statistical study. Enhancing the representativeness of the sample would be more appropriate for a comprehensive empirical analysis, which lies outside the scope of this paper. 

Comment 2:

Additionally, the title of Table 1 should be corrected for clarity: Table 1. g CO2eq Emissions Across Meal Types Within Each District Used for Policy Modeling. Values Are Shaded When Recipes Were Imputed From Other Districts.

Response 2:

Thank you for your constructive feedback regarding the clarity of Table 1. To address reviewer concerns, we have changed the table so there are no longer shaded values.  We believe these changes will make the table more understandable and allow it to stand alone more effectively, in line with best practices for academic presentations. Thank you again for helping us improve the clarity and quality of our manuscript.

Comment 3:

In discussion: The paper lacks a clear calculation of the economic costs associated with these scenarios. It would also be valuable to explore how the proposed changes could impact children's health and promote healthy eating habits. The authors should include an analysis of the economic feasibility of the recommended products and their availability in school districts. Furthermore, it is essential to address the expected acceptance of these dietary changes and student behaviors toward the proposed meal scenarios.

Response 3:

We appreciate your suggestion to explore the economic costs/feasibility and health impacts of the proposed policy changes.

While we agree that both the economic and health factors are critical to understanding the broader implications of these policies, our study was primarily focused on the environmental and nutritional aspects, specifically carbon emissions and adherence to existing nutritional standards. Estimation of economic costs would require information on many types of costs and include direct expenses such as food, labor and equipment depreciation, and indirect expenses such as rent, utilities, and administrative costs. In addition, there are several models for estimating economic costs, some of which involve estimating opportunity costs and benefits to society including long-term healthcare savings and impacts on local economies related to waste management and disposal. Such analysis would require additional data and warrant a separate study. Similarly, while we recognize that the proposed changes could significantly promote healthy eating habits and improve children's health, assessing these outcomes would require detailed data on student health and eating behaviors, which is outside the scope of this paper.

Given the complexity of both areas, we believe these topics would be better suited for future research, either in follow-up studies or in collaboration with experts in economics and public health. We look forward to expanding on these important aspects in subsequent work and will include a paragraph in the paper acknowledging their significance, highlighting the need for further research to explore these areas in more depth.

We added the following paragraph to the end of the conclusion: 

“While this study focused on carbon emissions and adherence to existing nutritional standards, economic and health factors are equally important for understanding the broader implications of the proposed policy changes. Some relevant work related to these factors has already been done.  Future research should examine the financial feasibility of such changes, including potential cost savings from sourcing plant-based foods, operational changes, and potential impacts on local food and waste systems. Additionally, health outcomes, such as childhood nutrition, and long-term dietary habits, warrant further investigation. While more research is necessary, some relevant work in this area has already been done. A 2017 case study by Friends of the Earth, in partnership with the Oakland Unified School District, assessed the carbon and water footprints of food procurement over two years, comparing the 2012-2013 baseline year with 2014-2015. The study found that by shifting towards less meat, better meat options, and increasing vegetables and legumes, the district reduced animal product purchases by nearly 30%. This led to a 14% reduction in the carbon footprint per meal, saving approximately 600,000 kg of CO2 annually (equivalent to driving 1.5 million fewer miles each year). Additionally, the district saved $42,000, or 1% per meal, while increasing the amount of fruits, vegetables, and legumes by 10%, and serving meals that met or exceeded USDA meal pattern standards. Such studies demonstrate the economic, environmental, and health benefits of rethinking food procurement and menu selection in institutional settings, and serve as a foundation for future research.”

 

Comment 4:

In conclusions, In Line 507, the authors discuss a food waste reduction strategy. It would be helpful to highlight the economic significance of reducing food waste as part of the conclusions. This addition would provide a more comprehensive perspective on the potential benefits of the proposed changes.

Response 4:

Our response to comment 3 covers this concern.  Please see  response to Comment 3, including the long paragraph we added.

Reviewer 4 Report

Comments and Suggestions for Authors

This paper focuses on the carbon footprint of American school lunch, and the research is very meaningful. However, there are many details that need to be refined in this article:

First, the introduction needs to explain the practical significance of this paper more fully, and the marginal innovation of this paper needs to be more clear;

Second, the representativeness of sample selection needs to be strengthened

Thirdly, in the last part, some countermeasures and suggestions need to be added

Fourth, the format needs to pay attention to why some comments in the submission have not been deleted.

Major revision are recommended.

Author Response

Reviewer 4:

Comment 1:

This paper focuses on the carbon footprint of American school lunch, and the research is very meaningful. However, there are many details that need to be refined in this article:

First, the introduction needs to explain the practical significance of this paper more fully, and the marginal innovation of this paper needs to be more clear;

Response 1:

Thank you for your insightful comments regarding the need for clearer exposition of the practical significance and innovative aspects of our study in the introduction. Based on your feedback, we have added a new paragraph to the introduction that elaborates on the practical significance of our research and clearly outlines its innovative contributions. This addition is designed to better contextualize our objectives and highlight how our findings can inform policy decisions and contribute to the development of more sustainable and nutritionally adequate school lunch programs. We believe this enhancement will make the aims and implications of our research more accessible and compelling to our readers.

Added paragraph:

“The primary goal of this paper is to explore potential impacts, propose actionable recommendations, and provide a framework for policy implementation. While the sample selection may not be representative of all possible scenarios, it serves as a practical illustration to support the policy argument rather than a definitive, scalable statistical study. Further, this paper bridges the gap between broader environmental policy discussions and actionable, localized changes in school meal programs.”

Comment 2:

Second, the representativeness of sample selection needs to be strengthened

Response 2:

Thank you for your thoughtful feedback. We would like to clarify that this paper is intended as a policy paper rather than a large-scale statistical analysis. Its primary aim is to explore potential impacts, propose actionable recommendations, and provide a practical framework for implementation. While the sample selection may not fully represent all possible scenarios, it serves as an illustrative example to support the policy argument rather than functioning as a definitive or scalable statistical study. Enhancing the representativeness of the sample would be more appropriate for a comprehensive empirical analysis, which lies outside the scope of this paper. We appreciate your input and will ensure this distinction is made clearer in the text.

Comment 3:

Thirdly, in the last part, some countermeasures and suggestions need to be added

Response 3:

We appreciate the suggestion. We have added text to that effect at the end of the paper: “While this study focused on carbon emissions and adherence to existing nutritional standards, economic and health factors are equally important for understanding the broader implications of the proposed policy changes. Future research should examine the financial feasibility of such changes, including potential cost savings from sourcing plant-based foods, operational changes, and potential impacts on local food waste systems. Additionally, health outcomes, such as childhood nutrition and long-term dietary habits, warrant further investigation. Collaborative efforts with economists and public health experts could offer a more comprehensive understanding and enhance the findings presented here.”

Comment 4:

Fourth, the format needs to pay attention to why some comments in the submission have not been deleted.

Response 4:

Thank you for pointing out the oversight regarding the comments in our submitted draft. We have thoroughly reviewed the document and removed all editorial comments to ensure that the revised draft is clean and meets the submission standards. We appreciate your attention to detail and apologize for any confusion this may have caused. The current submission has been updated to reflect a more polished and final version of our manuscript.

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

My opinion of this article remains the same, because the changes that have been made do not alter the serious error of this article. The article is based on the wrong premises, because the authors consider the process of raising cattle to be a source of carbon emissions, which is not true. There are many studies that show with strong evidence that raising cattle is not a source of carbon emissions.

Author Response

We definitely respectfully disagree.  While there are a few studies showing regenerative agriculture to be beneficial, there are many, many studies acknowledging that ruminant animals like cows, sheep, and goats produce methane as part of their natural metabolism.  Methane is a far more potent greenhouse gas than carbon dioxide.   There are no reputable reports to my knowledge claiming that feedlot cattle are not detrimental to the environment.   School lunches would not be procuring the type of beef that may have been written about as having benefits with respect to carbon footprint.

Please see the consensus IPCC Report, "Livestock's Long Shadow."

Reviewer 2 Report

Comments and Suggestions for Authors

Since the authors accepted most of my suggestions, I leave the possibility that some were not accepted, but with an appropriate explanation.
However, before the final fitting, I have to ask a few more things:
In the Methodology section, please add a paragraph that explains which statistical methods and which statistical tool were used.
I also ask that it be clearly stated in the methodology that all meals were isocaloric, since this is important for going through the manuscript.
I also ask that statistical significance be clearly emphasized in Table 1.
After these corrections are made, I consider the paper suitable for publication.

Author Response

Comment 1: Since the authors accepted most of my suggestions, I leave the possibility that some were not accepted, but with an appropriate explanation.
However, before the final fitting, I have to ask a few more things:
In the Methodology section, please add a paragraph that explains which statistical methods and which statistical tool were used.

Response 1:  We agree and have added the following to the Methods section:

Meals were grouped by category (plant-based, poultry, etc.) and differences in carbon footprint between the types of meals were tested for significance using the Student’s t-test.

Comment 2: I also ask that it be clearly stated in the methodology that all meals were isocaloric, since this is important for going through the manuscript.

Response 2: We have adjusted Table 2 to make this more clear.

Comment 3: I also ask that statistical significance be clearly emphasized in Table 1.  After these corrections are made, I consider the paper suitable for publication.

Response 3: Table 1 has a line for each meal type, with average and STDEV given.  We couldn't see a practical way to show the differences between the various groups within this framework. So, we thought that the best way to emphasize the results was to bold the p values in the text.

 

 

 

 

Reviewer 4 Report

Comments and Suggestions for Authors

It is worth affirming that the author has made relatively good revisions based on the previous suggestions. Here are two more suggestions for further improvement.First, the clarity of the images is insufficient and needs to be improved. Second, the shortcomings of this article and future progress need to be elaborated further, including the limitations of the sampling samples and the conclusions of this article, as well as possible cross-cultural comparative studies to be conducted in the future, etc. It is suggested that after minor revisions, this article be accepted for publication.

Author Response

Comment 1: It is worth affirming that the author has made relatively good revisions based on the previous suggestions. Here are two more suggestions for further improvement.

Response 1:  We are grateful for this acknowledgement and for the continued work to help us improve.

Comment 2:  First, the clarity of the images is insufficient and needs to be improved.

Response 2: We are so sorry, we have done our best with the resolution and will happily provide the original files if needed in the processing step.  

Comment 2: Second, the shortcomings of this article and future progress need to be elaborated further, including the limitations of the sampling samples and the conclusions of this article, as well as possible cross-cultural comparative studies to be conducted in the future, etc. It is suggested that after minor revisions, this article be accepted for publication.

Response 3: We have added a large section that covers meal palatability as well as ideas for incorporating the meal change along with educational information and experiential learning.    We also augmented the following sentence on culturally appropriate food: 

"Finally, additional assessment of the impact of serving culturally relevant meals including plant-based alternatives to beef that meet the regional needs of students in diverse (and often low-income) areas may prove useful. These are often also the communities most impacted by emissions pollution from food production."