The Impacts of Dietary Change on Greenhouse Gas Emissions, Land Use, Water Use, and Health: A Systematic Review

What is on plates for school meals: focusing on animal- vs. plant-based protein foods

BACKGROUND/OBJECTIVES

This study aimed to analyze the potential of school meals in South Korea as a sustainable tool to reduce carbon emissions by focusing on animal- vs. plant-based protein foods.

MATERIALS/METHODS

By using a stratified proportional allocation method, 536 out of the 11,082 schools nationwide were selected including 21 kindergartens, 287 elementary-, 120 middle- and 108 high schools. A total of 2,680 meals served for 5 consecutive days (June 21-25, 2021) were collected. We analyzed the average serving amounts of protein foods (animal- vs. plant-based) per meal and then, calculated the estimated average amounts of carbon emission equivalents per meal by applying the conversion coefficients. The t-test and analysis of variance were used for statistical analyses (α = 0.05).

RESULTS

The average serving amount of animal-based protein foods per meal was 12.5 g, which was approximately 3 times higher than that of plant-based ones (3.8 g) (P < 0.001); the Meat-group had the highest average amount of 17.0 g, followed by Egg-group (9.6 g), Fish-group (7.6 g), and Beans-and-Nuts-group (3.8 g) (P < 0.05). Specifically, pork (25.1 g) was ranked first, followed by poultry (19.6 g), processed meat products (18.0 g). The estimated average amount of carbon emission equivalents of animal-based protein foods per meal was 80.1 g CO2e, which was approximately 31 times higher than that of plant-based ones (2.6 g CO2e) (P < 0.001); the Meat-group had the highest average amount of 120.3 g CO2e, followed by Fish-group (44.5 g CO2e), Egg-group (25.9 g CO2e), and Beans-and-Nuts-group (2.6 g CO2e) (P < 0.05). Specifically, processed meat products (270.8 g CO2e) were ranked first, followed by pork (91.7 g CO2e), and processed fish products (86.6 g CO2e).

CONCLUSIONS

The results implied that school meals with plant-based alternatives could be a sustainable tool to improve carbon footprint.

Occupational therapy's contributions to combating climate change and lifestyle diseases

BACKGROUND

The interdependence between human occupations, lifestyle diseases and climate change provides an opportunity to address them simultaneously. Occupational therapists' training in lifestyle modification and knowledge about the impact of the physical environment on daily occupations puts them in a unique position to contribute to global efforts of combating climate change and lifestyle diseases through the promotion of sustainable occupations.

AIM

To illustrate how occupational therapists can contribute to global efforts of combating climate change and lifestyle diseases by framing climate change from a personal and public health perspective.

METHOD

In this discussion paper we argue that occupational therapists can use education and lifestyle modification to support individuals in the prevention and management of lifestyle diseases and that they can help design and advocate for environments that promote sustainable occupations.

RESULT

This discussion paper highlights the contributions that occupational therapists can make to how we understand and address climate change and lifestyle diseases.

CONCLUSIONS AND SIGNIFICANCE

We argue that by framing the climate change discourse from a health perspective, occupational therapists can contribute to global efforts of combating climate change and lifestyle diseases by supporting individuals to engage in sustainable occupations and communities to facilitate this engagement.

An ecological network approach for detecting and validating influential organisms for rice growth

How to achieve sustainable food production while reducing environmental impacts is a major concern in agricultural science, and advanced breeding techniques are promising for achieving such goals. However, rice is usually grown under field conditions and influenced by surrounding ecological community members. How ecological communities influence the rice performance in the field has been underexplored despite the potential of ecological communities to establish an environment-friendly agricultural system. In the present study, we demonstrate an ecological-network-based approach to detect potentially influential, previously overlooked organisms for rice (Oryza sativa). First, we established small experimental rice plots, and measured rice growth and monitored ecological community dynamics intensively and extensively using quantitative environmental DNA metabarcoding in 2017 in Japan. We detected more than 1000 species (including microbes and macrobes such as insects) in the rice plots, and nonlinear time series analysis detected 52 potentially influential organisms with lower-level taxonomic information. The results of the time series analysis were validated under field conditions in 2019 by field manipulation experiments. In 2019, we focused on two species, Globisporangium nunn and Chironomus kiiensis, whose abundance was manipulated in artificial rice plots. The responses of rice, namely, the growth rate and gene expression patterns, were measured before and after the manipulation. We confirmed that, especially in the G. nunn-added treatment, rice growth rate and gene expression pattern were changed. In the present study, we demonstrated that intensive monitoring of an agricultural system and the application of nonlinear time series analysis were helpful to identify influential organisms under field conditions. Although the effects of the manipulations were relatively small, the research framework presented here has future potential to harness the ecological complexity and utilize it in agriculture. Our proof-of-concept study would be an important basis for the further development of field-basis system management.

Sustainable Isolation of Bioactive Compounds and Proteins from Plant-Based Food (and Byproducts)

Plant-based food produces significantly less greenhouse gases, and due to its wealth of bioactive components and/or plant-based protein, it becomes an alternative in a sustainable food system. However, the processing and production of products from plant sources creates byproducts, which can be waste or a source of useful substances that can be reused. The waste produced during the production and processing of food is essentially nutrient- and energy-rich, and it is recognized as an excellent source of secondary raw materials that could be repurposed in the process of manufacturing and preparing food, or as feed for livestock. This review offers an overview of the sources and techniques of the sustainable isolation of bioactive substances and proteins from various sources that might represent waste in the preparation or production of food of plant origin. The aim is to uncover novel approaches to use waste and byproducts from the process of making food to provide this waste food an additional benefit, not forgetting the expectations of the end user, the consumer. For the successful isolation of bioactive ingredients and proteins from food of plant origin, it is crucial to develop more eco-friendly and efficient extraction techniques with a low CO2 footprint while considering the economic aspects.

Improving school lunch menus with multi-objective optimisation: nutrition, cost, consumption and environmental impacts

OBJECTIVE

To support school foods programmes by evaluating the relationship between nutritional quality, cost, student consumption and the environmental impacts of menus.

DESIGN

Using linear programming and data from previously served menu items, the relationships between the nutritional quality, cost, student consumption and the environmental impacts of lunch menus were investigated. Optimised lunch menus with the maximum potential student consumption and nutritional quality and lowest costs and environmental impacts were developed and compared with previously served menus (baseline).

SETTING

Boston Public Schools (BPS), Boston Massachusetts, USA.

PARTICIPANTS

Menu items served on the 2018-2019 BPS lunch menu (n 142).

RESULTS

Using single-objective models, trade-offs were observed between most interests, but the use of multi-objective models minimised these trade-offs. Compared with the current weekly menus offered, multi-objective models increased potential caloric intake by up to 27 % and Healthy Eating Index scores by up to 19 % and reduced costs and environmental impacts by up to 13 % and 71 %, respectively. Improvements were made by reducing the frequency of beef and cheese entrées and increasing the frequency of fish and legume entrées on weekly menus.

CONCLUSIONS

This work can be extrapolated to monthly menus to provide further direction for school districts, and the methods can be employed with different recipes and constraints. Future research should test the implementation of optimised menus in schools and consider the broader implications of implementation.

A Comprehensive Analysis of the Nutritional Composition of Plant-Based Drinks and Yogurt Alternatives in Europe

Concerns for human and planetary health have led to a shift towards healthier plant-based diets. Plant-based dairy alternatives (PBDA) have experienced exponential market growth due to their lower environmental impact compared to dairy products. However, questions have arisen regarding their suitability as dairy substitutes and their role in food-based dietary guidelines (FBDG). Our study aimed to analyse the nutritional profiles of leading PBDA across Europe and compare them with their dairy counterparts. We examined the nutritional profiles of 309 unflavoured PBDA representing the European market leaders, including 249 plant-based drinks (PBD) and 52 plant-based alternatives to yogurt (PBAY). PBD and PBAY, excluding coconut varieties, were low in saturated fat (<1 g per serving). Seventy percent of PBDA were unsweetened, and most had sugar levels comparable to dairy. Except for soya varieties, PBDA protein levels were lower than dairy. Organic PBDA lacked micronutrients due to legal restrictions on fortification. Among non-organic PBDA, 76% were fortified with calcium, 66% with vitamin D, and 60% with vitamin B12. Less than half were fortified with vitamin B2, and a few with iodine (11%) and vitamin A (6%). PBAY were less frequently fortified compared to PBD. PBDA displayed a favourable macronutrient profile despite lower protein levels, which would be compensated for by other protein-dense foods in a usual mixed diet. Enhancing fortification consistency with dairy-associated micronutrients would address concerns regarding PBDA's integration into FBDG. Our analysis supports the inclusion of fortified PBDA in environmentally sustainable FBDG for healthy populations.

Vegans, vegetarians, fish-eaters and meat-eaters in the UK show discrepant environmental impacts

Modelled dietary scenarios often fail to reflect true dietary practice and do not account for variation in the environmental burden of food due to sourcing and production methods. Here we link dietary data from a sample of 55,504 vegans, vegetarians, fish-eaters and meat-eaters with food-level data on greenhouse gas emissions, land use, water use, eutrophication risk and potential biodiversity loss from a review of 570 life-cycle assessments covering more than 38,000 farms in 119 countries. Our results include the variation in food production and sourcing that is observed in the review of life-cycle assessments. All environmental indicators showed a positive association with amounts of animal-based food consumed. Dietary impacts of vegans were 25.1% (95% uncertainty interval, 15.1-37.0%) of high meat-eaters (≥100 g total meat consumed per day) for greenhouse gas emissions, 25.1% (7.1-44.5%) for land use, 46.4% (21.0-81.0%) for water use, 27.0% (19.4-40.4%) for eutrophication and 34.3% (12.0-65.3%) for biodiversity. At least 30% differences were found between low and high meat-eaters for most indicators. Despite substantial variation due to where and how food is produced, the relationship between environmental impact and animal-based food consumption is clear and should prompt the reduction of the latter.

Bioactive compounds for human and planetary health

Bioactive compounds found in edible plants and foods are vital for human and planetary health, yet their significance remains underappreciated. These natural bioactives, as part of whole diets, ingredients, or supplements, can modulate multiple aspects of human health and wellness. Recent advancements in omic sciences and computational biology, combined with the development of Precision Nutrition, have contributed to the convergence of nutrition and medicine, as well as more efficient and affordable healthcare solutions that harness the power of food for prevention and therapy. Innovation in this field is crucial to feed a growing global population sustainably and healthily. This requires significant changes in our food system, spanning agriculture, production, distribution and consumption. As we are facing pressing planetary health challenges, investing in bioactive-based solutions is an opportunity to protect biodiversity and the health of our soils, waters, and the atmosphere, while also creating value for consumers, patients, communities, and stakeholders. Such research and innovation targets include alternative proteins, such as cellular agriculture and plant-derived protein; natural extracts that improve shelf-life as natural preservatives; upcycling of agricultural by-products to reduce food waste; and the development of natural alternatives to synthetic fertilizers and pesticides. Translational research and innovation in the field of natural bioactives are currently being developed at two levels, using a systems-oriented approach. First, at the biological level, the interplay between these compounds and the human host and microbiome is being elucidated through omics research, big data and artificial intelligence, to accelerate both discovery and validation. Second, at the ecosystem level, efforts are focused on producing diverse nutrient-rich, flavorful, and resilient, yet high-yield agricultural crops, and educating consumers to make informed choices that benefit both their health and the planet. Adopting a system-oriented perspective helps: unravel the intricate and dynamic relationships between bioactives, nutrition, and sustainability outcomes, harnessing the power of nature to promote human health and wellbeing; foster sustainable agriculture and protect the ecosystem. Interdisciplinary collaboration in this field is needed for a new era of research and development of practical food-based solutions for some of the most pressing challenges humanity and our planet are facing today.

Sustainable choices of plant-based ('super') foods: examining the consumption patterns of German consumers on avocados

This paper aims to better understand consumer awareness of the environmental impact of plant-based ('super'-) foods, using avocados as an example. Since all food production impacts the environment, both meat-based and plant-based, there is scope for more sustainable food choices. Avocados have positive health properties while being considered critically for the potential negative environmental impact of their production. This study examines the avocado consumption behaviour of German consumers and the extent to which knowledge and dietary patterns are related to this. Data from 373 respondents from Germany were collected through an online consumer survey. Bivariate comparisons for avocado consumption and logistic regression analyses were performed to explore avocado consumption behaviour. The frequency of avocado consumption among respondents was moderate, averaging once per month. Avocado consumption was related to a flexitarian diet, older age and higher income, and urban dwellers. Knowledge of the environmental impacts of avocado cultivation had no influence. Respondents' self-assessed knowledge about avocados was low. To help consumers in making conscious, sustainable choices for plant-based foods, it is necessary to provide accessible and comparable information on the environmental impact of food products. However, further life cycle assessments on avocado production are clearly needed in order to produce valid information material. A flexitarian diet with reduced consumption of animal foods is an important prerequisite for environmental sustainability. Drawing attention to environmentally friendly plant-based food choices for flexitarian consumers could further encourage them to become food innovators for a healthy planet by reducing climate impact, land use, and energy and water consumption.

The use of environmental scenarios to project future health effects: a scoping review

Environmental risks are a substantial factor in the current burden of disease, and their role is likely to increase in the future. Model-based scenario analysis is used extensively in environmental sciences to explore the potential effects of human activities on the environment. In this Review, we examine the literature on scenarios modelling environmental effects on health to identify the most relevant findings, common methods used, and important research gaps. Health outcomes and measures related to climate change (n=106) and air pollution (n=30) were most frequently studied. Studies examining future disease burden due to changes or policies related to dietary risks were much less common (n=10). Only a few studies assessed more than two environmental risks (n=3), even though risks can accumulate and interact with each other. Studies predominantly covered high-income countries and Asia. Sociodemographic, vulnerability, and health-system changes were rarely accounted for; thus, assessing the full effect of future environmental changes in an integrative way is not yet possible. We recommend that future models incorporate a broader set of determinants of health to more adequately capture their effect, as well as the effect of mitigation and adaptation efforts.

Predicting the Adoption of a Sustainable Diet in Adults: A Cross-Sectional Study in Italy

Shifting food choices towards sustainability entails the analysis of dietary behavior determinants. This study aimed to explain and predict the intention to follow a sustainable diet and its adoption in a representative sample of adults (n = 838) in Italy. An online survey based on the theory of planned behavior (TPB) was developed. The adoption of a sustainable diet was measured as self-perceived behavior, adherence to the Mediterranean diet (MD), and food consumption frequencies. Psychometric analysis and correlations between attitude, subjective norms, and perceived behavioral control (PBC) with both intention and behavior assessments were evaluated. Structural equation models were used to test whether and to what extent attitude, subjective norms, and PBC explained intention and behavior. Significant associations were found between TPB constructs and the behavior measures underlining the main role of intention and PBC in affecting behavior. The applied TPB models explained behavioral intention at most (78%). The results suggested promising interventions in narrowing the attitude-behavior gap to encourage specific adult population groups in Italy to adopt virtuous food consumption habits. Beside the implementation of price mechanism strategies, educational initiatives to increase awareness about food and diet sustainability issues and the reinforcement of the perceived control on food consumption at the individual level are recommended.

The Bahraini food based dietary guidelines: a holistic perspective to health and wellbeing

The impact of food consumption extends well beyond the physical aspect of health to affect the mind, the society, and the environment. The biopsycho-ecological (BSE) theory recognizes the interplay between these factors and emphasizes the need for a holistic perspective to dietary recommendations. This manuscript presents a situation analysis of food consumption and diet-related diseases in Bahrain and describes the themes of the Bahraini Food based dietary guidelines (FBDG) and their alignment with the BSE constructs. Available data revealed low fruit and vegetable intake and excessive consumption of processed meat and sugary drinks in the country. These dietary habits are accompanied by a high burden of non-communicable diseases and their risk factors, anemia, and vitamin D deficiency. The Bahraini FBDG consisted of 11 context-specific themes and key messages that addressed the four dimensions of health depicted by the BSE theory, as follows: diet, physical activity, and food safety (body), physical activity, mindful eating and mental health (mind); family relations and cultural heritage (society), and food waste and environmental footprints of dietary intake (environment). The Bahraini FBDG present a model of dietary guidelines that adopted a holistic perspective to address health as they promote the role of food and dietary habits in maintaining the health of the body and that of the mind, the society, and the environment.

Evaluation of the fermentation potential of lactic acid bacteria isolated from herbs, fruits and vegetables as starter cultures in nut-based milk alternatives

Fermentation of plant-based milk alternatives (PBMAs), including nut-based products, has the potential to generate new foods with improved sensorial properties. In this study, we screened 593 lactic acid bacteria (LAB) isolates from herbs, fruits and vegetables for their ability to acidify an almond-based milk alternative. The majority of the strongest acidifying plant-based isolates were identified as Lactococcus lactis, which were found to lower the pH of almond milk faster than dairy yoghurt cultures. Whole genome sequencing (WGS) of 18 plant-based Lc. lactis isolates revealed the presence of sucrose utilisation genes (sacR, sacA, sacB and sacK) in the strongly acidifying strains (n = 17), which were absent in one non-acidifying strain. To confirm the importance of Lc. lactis sucrose metabolism in efficient acidification of nut-based milk alternatives, we obtained spontaneous mutants defective in sucrose utilisation and confirmed their mutations by WGS. One mutant containing a sucrose-6-phosphate hydrolase gene (sacA) frameshift mutation was unable to efficiently acidify almond, cashew and macadamia nut milk alternatives. Plant-based Lc. lactis isolates were heterogeneous in their possession of the nisin gene operon near the sucrose gene cluster. The results of this work show that sucrose-utilising plant-based Lc. lactis have potential as starter cultures for nut-based milk alternatives.

Should Men Eat More Plants? A Systematic Review of the Literature on the Effect of Plant-Forward Diets on Men's Health

OBJECTIVE

To perform a systematic review of the literature on plant-based and plant-forward diets and the prevention/treatment of the following common men's health conditions: prostate cancer (PCa), erectile dysfunction (ED), and benign prostatic hyperplasia (BPH).

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses system criteria were utilized to search PubMed and Medline databases for the following search terms: "Diet (Mesh)" OR "Diet Therapy (Mesh)" AND "Prostatic Hyperplasia (Mesh)" OR "Prostatic Neoplasm (Mesh)" OR "Erectile Dysfunction (Mesh)." Articles in English published from 1989 to 2022 using human participants were analyzed, data summarized, and assessed for bias.

RESULTS

Studies reporting on plant-based or vegetable-forward diets (Mediterranean) as an intervention were included. Cohort and cross-sectional studies using food frequency questionnaires or diet classification indices to quantify plant-based food intake patterns were included in the study. Ultimately, 12 PCa articles, 4 BPH articles, 6 ED articles, and 2 articles related to both BPH and ED were reviewed. Overall, the literature suggests plant-forward diets confer a protective effect on the men's health conditions reviewed.

CONCLUSIONS

Evaluation of the literature on the impact of plant-forward diets on urologic conditions includes a heterogenous range of dietary patterns and study designs. The greatest amount of research has evaluated the application of plant-forward diets for PCa. While there is currently a lack of high-quality evidence for the use of plant-forward diets as prevention and/or treatment for PCa, ED, or BPH, reported outcomes suggest a consistent small beneficial impact alongside well-established benefits for common chronic conditions.

Low-carbon diets can reduce global ecological and health costs

Potential external cost savings associated with the reduction of animal-sourced foods remain poorly understood. Here we combine life cycle assessment principles and monetarization factors to estimate the monetary worth of damage to human health and ecosystems caused by the environmental impacts of food production. We find that, globally, approximately US$2 of production-related external costs were embedded in every dollar of food expenditure in 2018-corresponding to US$14.0 trillion of externalities. A dietary shift away from animal-sourced foods could greatly reduce these 'hidden' costs, saving up to US$7.3 trillion worth of production-related health burden and ecosystem degradation while curbing carbon emissions. By comparing the health effects of dietary change from the consumption versus the production of food, we also show that omitting the latter means underestimating the benefits of more plant-based diets. Our analysis reveals the substantial potential of dietary change, particularly in high and upper-middle-income countries, to deliver socio-economic benefits while mitigating climate change.

Insight into the Sustainability of the Mediterranean Diet: The Water Footprint of the Recommended Italian Diet

At present, as we face climate change and natural resource scarcity, one of the major challenges linking humans and the environment is to ensure sufficient, nutritious, safe, and affordable food for a rapidly growing world population. In a nutshell, "feed the world without destroying it". The water footprint (WF), i.e., the withdrawals of fresh water necessary to produce one kilogram of food product, is one of the key indicators of the environmental impact of diets. In this work, the WF of the food patterns suggested by the Italian Food Based Dietary Guidelines, considered a model of the Mediterranean Diet, was evaluated for the first time. The data reported here clearly demonstrate that the suggested Italian dietary patterns have a low WF, the reduction of which by replacing animal foods with plant foods is limited because the suggested consumption of meat is already low. Consumer choice in the consumption of specific products within a food group could further reduce the WF of the diet, underlining the need to provide correct information not only to consumers but also to farmers and producers to encourage them to make water-saving choices.

PlantACT! - how to tackle the climate crisis

Greenhouse gas (GHG) emissions have created a global climate crisis which requires immediate interventions to mitigate the negative effects on all aspects of life on this planet. As current agriculture and land use contributes up to 25% of total GHG emissions, plant scientists take center stage in finding possible solutions for a transition to sustainable agriculture and land use. In this article, the PlantACT! (Plants for climate ACTion!) initiative of plant scientists lays out a road map of how and in which areas plant scientists can contribute to finding immediate, mid-term, and long-term solutions, and what changes are necessary to implement these solutions at the personal, institutional, and funding levels.

Transitioning to sustainable dietary patterns: learnings from animal-based and plant-based dietary patterns in French Canadian adults

Introduction

Many dietary guidelines promote the substitution of animal proteins with plant-based proteins for health benefits but also to help transitioning toward more sustainable dietary patterns. The aim of this study was to examine the food and nutrient characteristics as well as the overall quality and costs of dietary patterns consistent with lower intakes of animal-based protein foods and with higher intakes of plant-based protein foods among French Canadian adults.

Methods

Dietary intake data, evaluated with 24 h recalls, from 1,147 French-speaking adults of the PRÉDicteurs Individuels, Sociaux et Environnementaux (PREDISE) study conducted between 2015 and 2017 in Québec were used. Usual dietary intakes and diet costs were estimated with the National Cancer Institute's multivariate method. Consumption of animal- and plant-based protein foods was classified into quarters (Q) and differences in food and nutrient intakes, Healthy Eating Food Index (HEFI)-2019 scores and diet costs across quarters were assessed using linear regression models adjusted for age and sex.

Results

Participants with lower intakes of animal-based protein foods (Q1 vs. Q4) had a higher HEFI-2019 total score (+4.0 pts, 95% CI, 0.9 to 7.1) and lower daily diet costs (-1.9 $CAD, 95% CI, -2.6 to -1.2). Participants with higher intakes of plant-based protein foods (Q4 vs. Q1) had a higher HEFI-2019 total score (+14.6 pts, 95% CI, 12.4 to 16.9) but no difference in daily diet costs (0.0$CAD, 95% CI, -0.7 to 0.7).

Discussion

In a perspective of diet sustainability, results from this study among French-speaking Canadian adults suggest that a shift toward a dietary pattern focused primarily on lower amounts of animal-based protein foods may be associated with a better diet quality at lower costs. On the other hand, transitioning to a dietary pattern focused primarily on higher amounts of plant-based protein foods may further improve the diet quality at no additional cost.

Measurement of diets that are healthy, environmentally sustainable, affordable, and equitable: A scoping review of metrics, findings, and research gaps

Introduction

Research on the impacts of dietary patterns on human and planetary health is a rapidly growing field. A wide range of metrics, datasets, and analytical techniques has been used to explore the role of dietary choices/constraints in driving greenhouse gas (GHG) emissions, environmental degradation, health and disease outcomes, and the affordability of food baskets. Many argue that each domain is important, but few have tackled all simultaneously in analyzing diet-outcome relationships.

Methods

This paper reviews studies published between January 2015 and December 2021 (inclusive) that examined dietary patterns in relation to at least two of the following four thematic pillars: (i) planetary health, including, climate change, environmental quality, and natural resource impacts, (ii) human health and disease, (iii) economic outcomes, including diet cost/affordability, and (iv) social outcomes, e.g., wages, working conditions, and culturally relevant diets. We systematically screened 2,425 publications by title and abstract and included data from 42 eligible publications in this review.

Results

Most dietary patterns used were statistically estimated or simulated rather than observed. A rising number of studies consider the cost/affordability of dietary scenarios in relation to optimized environmental and health outcomes. However, only six publications incorporate social sustainability outcomes, which represents an under-explored dimension of food system concerns.

Discussion

This review suggests a need for (i) transparency and clarity in datasets used and analytical methods; (ii) explicit integration of indicators and metrics linking social and economic issues to the commonly assessed diet-climate-planetary ecology relationships; (iii) inclusion of data and researchers from low- and middle-income countries; (iv) inclusion of processed food products to reflect the reality of consumer choices globally; and (v) attention to the implications of findings for policymakers. Better understanding is urgently needed on dietary impacts on all relevant human and planetary domains simultaneously.

Plant-based and vegetarian diets: an overview and definition of these dietary patterns

PURPOSE

This paper aims to present an overview of the definitions of "plant-based and "vegetarian diets" adopted by different organizations worldwide, proposing new standard definitions and discussing the notion of vegetarianism as a restrictive dietary pattern.

METHODS

An extensive literature review on the different definitions of vegetarian and plant-based diets was conducted. Definitions of different international vegetarian and vegan organizations were also taken into account. Objective definitions for vegetarian and plant-based diets, as well as for their subcategories, were proposed. Other aspects related to how vegetarian diets are viewed and defined were also discussed.

RESULTS

We proposed that a vegetarian diet should be defined as "a dietary pattern that excludes meat, meat-derived foods, and, to different extents, other animal products". This definition would include, among others, ovolactovegetarian and vegan diets. The proposed definition for a plant-based diet was "a dietary pattern in which foods of animal origin are totally or mostly excluded". Other types of diets, such as flexitarian and pescetarian diets, could be considered plant-based. A vegetarian diet should not be considered restrictive. Instead, terms such as alternative or non-conventional could be used to define it and to distinguish it from the conventional diet adopted by most of the Western population.

CONCLUSION

This paper was able to elaborate objective definitions of vegetarian and plant-based diets. Standardizing nomenclatures may reduce misinterpretation and confusion in this field of study.

Higher adherence to the EAT-Lancet reference diet is associated with higher nutrient adequacy in the NutriNet-Santé cohort : a cross-sectional study

BACKGROUND

In 2019, the EAT-Lancet Commission proposed a planetary and healthy reference diet; however, its nutritional quality has been rarely evaluated.

OBJECTIVE

Across different adherence levels to the EAT-Lancet reference diet, the following were our objectives:1) describe the food and nutritional intakes of the French population, 2) to evaluate the nutrient quality and, 3) investigate the consistency between the French national recommendations and the EAT-Lancet reference diet.

DESIGN

This cross-sectional study was conducted among participants of the NutriNet-Santé cohort and the sample was weighted on the characteristics of the general French population. Adherence to the EAT-Lancet reference diet was estimated using the EAT-Lancet Diet Index (ELD-I). Usual nutrient intakes were obtained using the variance reduction method. We used the estimated average requirements cut-point method to estimate the proportion of participants who meet their respective nutritional requirements. Furthermore, the adequacy of the French food-based dietary recommendations (Programme National Nutrition Santé [PNNS]) according to adherence to the EAT-Lancet reference diet was studied.

RESULTS

The weighted sample was composed of 98,465 participants. Except for bioavailable zinc and vitamin B12, we observed a decrease in the nutrient inadequacy prevalence when the adherence to the EAT-Lancet reference diet increased, particularly for vitamin B9 (Q1=37.8% vs. Q5=5.5%, p=<0.0001) and vitamin C (Q1=59.0% vs. Q5=10.8 %, p=<0.0001). However, inadequacy prevalence remained high in all ELD-I quintiles, particularly for fiber (95.9%), vitamin B1 (70.8%), iodine (48.4%), and magnesium (76.8%). Higher ELD-I score was associated with higher adherence for most components of the PNNS, except for food groups that are not specifically included in the EAT-Lancet reference diet and are typical of the French diet, including alcohol, processed meat, and salt.

CONCLUSION

In the French context, although issues with the intake of certain nutrients may occur, a diet that remains within the planetary limits as the EAT-Lancet reference diet allows a favorable nutritional quality.

TRIAL REGISTRATION NUMBER

NCT03335644.

Popular diets as selected by adults in the United States show wide variation in carbon footprints and diet quality

BACKGROUND

Carbon footprints of vegetarian, pescatarian, and other popular diets have been studied previously, but mostly as idealized versions modeled to meet dietary recommendations. Less is known about the footprints of popular diets as they are consumed by US adults, and thus the potential trade-offs with diet quality for free-living individuals.

OBJECTIVES

This study estimated the carbon footprint and diet quality of popular diets as selected by a nationally representative sample of US consumers, including the recently trending keto- and paleo-style diets.

METHODS

The 2005-2010 NHANES 24-h recall data were used to categorize individual adult diets (n = 16,412) into 6 types: vegan, vegetarian, pescatarian, paleo, keto, and all other diets, referred to here as omnivore diets. Average daily greenhouse gas emissions in kilograms of carbon dioxide equivalents per 1000 kcal (kg CO2-eq/1000 kcal) were calculated for each diet by matching our previously developed database to NHANES individual diet data. Diet quality was determined using the Healthy Eating Index (HEI) and the Alternate Healthy Eating Index. Survey-weighted ordinary least-squares regression was used to assess mean differences in diets.

RESULTS

The average carbon footprints of vegan (0.69 ± 0.05 kg CO2-eq/1000 kcal) and vegetarian (1.16 ± 0.02) diets were lower (P < 0.05) than those of the pescatarian (1.66 ± 0.04), omnivore (2.23 ± 0.01), paleo (2.62 ± 0.33), or keto (2.91 ± 0.27) diets. Mean HEI scores were highest for pescatarian diets (58.76 ± 0.79) and higher (P < 0.05) for vegetarian (51.89 ± 0.74) than for omnivore (48.92 ± 0.33) or keto (43.69 ± 1.61) diets.

CONCLUSIONS

Our results highlight the nuances when evaluating the nutritional quality of diets and their carbon footprints. On average, pescatarian diets may be the healthiest, but plant-based diets have lower carbon footprints than other popular diets, including keto- and paleo-style diets.

Relationship between adherence to the Mediterranean diet, sustainable and healthy eating behaviors, and awareness of reducing the ecological footprint

This study evaluated the relationship between adherence to the Mediterranean diet (MD), sustainable and healthy eating behaviors, and awareness of reducing the ecological footprint. It was conducted with 1333 adults (38.2% male, 61.8% female, mean age 24.2 ± 7.5 years). The questionnaire included socio-demographic characteristics, anthropometric measurements, the Awareness Scale for Reducing Ecological Footprint (ASREF), the Sustainable and Healthy Eating (SHE) Behaviors Scale, and Mediterranean Diet Adherence Scale (MEDAS). 40.2% of the participants adhered to the MD (≥7 scores). Obese individuals' total scores on MEDAS, SHE Behaviors Scale, and ASREF were the lowest (p < 0.05). In regression analysis, education duration, SHE Behaviors Scale total score, and BMI affected the ASREF score (p < 0.05). The education duration, SHE Behaviors Scale scores, and ASREF scores were higher in those in MD-adherence group (p < 0.05). In conclusion, adherence to the MD was associated with higher sustainable and healthy eating behaviors and higher awareness of ecological footprint reduction.

Strategies for reducing meat consumption within college and university settings: A systematic review and meta-analysis

Introduction

Despite the considerable public and planetary health benefits associated with reducing the amount of meat consumed in high-income countries, there is a limited empirical understanding of how these voluntary changes in food choice can be effectively facilitated across different settings. While prior reviews have given us broad insights into the varying capacities of behavior change strategies to promote meaningful reductions in meat consumption, none have compared how they perform relative to each other within a uniform dining context.

Methods

To address this gap in the literature, we synthesized the available research on university-implemented meat reduction interventions and examined the variations in the success rates and effect estimates associated with each of the three approaches identified in our systematic review.

Results

From our analyses of the 31 studies that met our criteria for inclusion (n = 31), we found that most were successful in reducing the amount of meat consumed within university settings. Moreover, independent of the number of individual strategies being used, multimodal interventions were found to be more reliable and effective in facilitating these changes in food choice than interventions targeting the choice architecture of the retail environment or conscious decision-making processes alone.

Discussion

In addition to demonstrating the overall value of behavior change initiatives in advancing more sustainable dining practices on college and university campuses, this study lends further insights into the merits and mechanics underlying strategically integrated approaches to dietary change. Further investigations exploring the persistence and generalizability of these effects and intervention design principles are needed.

Systematic review registration

https://doi.org/10.17605/OSF.IO/DXQ5V, identifier: 10.17605/OSF.IO/DXQ5V.

Carbon footprint, economic benefits and sustainable fishing: Lessons for the future from the Western Mediterranean

Ensuring an economically viable, sustainable and low CO₂ emission extractive fishery is critical in order to achieve the life below water UN sustainable development goals and the climate change commitments of Paris agreement. This challenge is even more relevant in the most overexploited region of the world: The Mediterranean Sea. Here, we use the socio-ecological system of the Spanish Mediterranean commercial fisheries (Northern Alboran Sea, Northern Spain and the Balearic Islands) to develop an integrative impact assessment, including detailed socio-economic, ecosystem indices of the trophic structure of extractive fishery and CO₂ emission analyses combining different gear, vessel size classes as well as a wide range estimation of carbon release from the seafloor by bottom trawling. Northern Alboran Sea preferentially requires reduction in purse seine fishery while in Northern Spain bottom trawling should be reduced first to reach sustainable exploitation. Fuel CO₂ footprint of purse seine and bottom trawling are among the lowest footprints of animal protein production, but considering sweeping released CO₂ from the seafloor the bottom trawling footprint becomes the animal protein production with the highest footprint. Moreover, the lowest bottom released CO₂ estimation overrides 2.7-10 times the CO₂ buried in the seafloor through the biological pump in trawled areas potentially turning the continental shelf from a CO₂ sink to a CO₂ source. Net profit per fuel derived CO₂ emission for all fleets is lower than 1€ kgCO₂^-1, being lowest for large bottom trawler (0.025 € kgCO₂^-1). Thus, urgent mitigation and adaptation measures are necessary to obtain sustainable fishery in terms of net profit, sustainable seafood extraction and CO₂ emission reduction. Our study provides scientific bases to develop these measures such as the restriction of harmful fishing gear in carbon rich river influenced areas, reduction of bottom contact of the fishing gear, favouring purse seine fishery and smaller bottom trawlers.

The Environmental Sustainability of Plant-Based Dietary Patterns: A Scoping Review

BACKGROUND

A large part of the existential threat associated with climate change is the result of current human feeding patterns. Over the last decade, research evaluating the diet-related environmental impacts of plant-based diets has emerged, and a synthesis of the available data is now due.

OBJECTIVES

The objectives of the study were as follows: 1) to compile and summarize the literature on diet-related environmental impacts of plant-based dietary patterns; 2) to assess the nature of the data on impacts of plant-based dietary patterns on both environmental parameters and health (e.g., if land use is reduced for a particular diet, is cancer risk also reduced?); and 3) to determine where sufficient data exist for meta-analyses, in addition to identifying gaps within the literature.

METHODS

Global peer-reviewed studies on the environmental impacts of plant-based diets were searched in Ovid MEDLINE, EMBASE, and Web of Science. After removing duplicates, the screening identified 1553 records. After 2 stages of independent review by 2 reviewers, 65 records met the inclusion criteria and were eligible to be used in synthesis.

RESULTS

Evidence suggests that plant-based diets may offer lower greenhouse gas emissions (GHGEs), land use, and biodiversity loss than offered by standard diets; however, the impact on water and energy use may depend on the types of plant-based foods consumed. Further, the studies were consistent in demonstrating that plant-based dietary patterns that reduce diet-related mortality also promote environmental sustainability.

CONCLUSIONS

Overall, there was agreement across the studies regarding the impact of plant-based dietary patterns on GHGE, land used, and biodiversity loss despite varied plant-based diets assessed.

Assessing the interlinkage between biodiversity and diet through the Mediterranean diet case

The adoption of healthy and sustainable diets, and the transition to sustainable food systems is of principal importance in order to counteract the double burden of climate change and non-communicable diseases. The Mediterranean diet (MD) has been widely recognized as a biodiversity and healthy nutrition resource to support sustainable development and food security. This study explored biodiversity in terms of food plants species, subspecies, varieties and races, and also addressed food-plant diversity differences between the MD and western-type consumption patterns. It was funded by the EU BioValue Project, aiming to promote the integration of underutilized crops into the food value chains. Using a two-stage scheme, data were selected from MEDUSA and Euro+Med databases (including 449 species, 2,366 subspecies, varieties, and races). Furthermore, 12 countries from North Africa and Europe were classified in two groups according to their sub-regional attributes and their traditionally most prevalent dietary pattern (MD or western-type diets). Statistical analysis showed that the mean of the majorly cultivated food plants in the MD was significantly higher than its counterpart in the Western-diet. Furthermore, no statistical difference was detected in the averages of native food plants between the MD group and the Western diet group, implying that the higher diversity in food plants observed in the MD seems to be attributed to crop utilization rather than crop availability. Our findings indicated the interlinkage between biodiversity and prevailing dietary patterns, and further underlined that biodiversity could constitute a prerequisite for dietary diversity, and hence nutrition security. In addition, this study demonstrated that diets and nutrition should be approached in a broader way within the context of both agro-food and ecological systems.

The role of family medicine and primary health care and its impact on the climate crisis

No abstract available.

Consumers' attitudes towards alternatives to conventional meat products: Expectations about taste and satisfaction, and the role of disgust

The livestock sector has environmental, health, and animal welfare impacts. This UK-based, quantitative study aimed to elucidate consumers' valuation of alternatives to conventional meat products. In an online study, 151 meat eaters and 44 non-meat eaters were shown pictures of meat, dairy, and bakery products, including beef burger, cheese sandwich and blueberry muffin. Each product was evaluated with three different labels (e.g., 'conventional', 'plant-based' and 'cultured' for beef burger). Participants rated expected taste pleasantness, fullness, satisfaction, healthiness, disgust and willingness-to-pay for each product/label combination. The results obtained demonstrate that alternatives to conventional meat products overall are acceptable to both meat and non-meat eaters. Although meat eaters' expected plant-based meat alternatives to be less satisfying, due to lower expected taste pleasantness and fillingness (Cohen's d = 0.14 to 0.63), they perceived the plant-based alternatives to be more healthy (d ≥ 1.18). Cultured meat products were perceived by meat eaters to be equally or more healthy, but more disgusting (d ≥ 0.41), than conventional meat products. These results suggest there is an opportunity to promote (motivate) acceptance of alternatives to conventional meat products based on their perceived healthiness, to at least partly balance reduced expected taste pleasantness and other negative attributes (i.e., barriers).

Dietary modeling of greenhouse gases using OECD meat consumption/retail availability estimates

Research has demonstrated different carbon footprints, based on portion estimations. However, previous estimates are low and often omit the impact of food waste. For example, a high-level of daily meat consumption has been estimated at 100 g, which is less than a typical “quarter pounder” hamburger. We used the Organization for Economic Co-operation and Development (OECD) annual estimates of national retail availability, and applied a mathematical model to prorate other research results to determine a meat portion equal to current OECD statistics, and also projected the diets to 2500 and 3250 kcal, to include consumer and retail waste. Once prorated, the 14 national studies are contrasted and analyzed for reasonableness against OECD data pertaining to U.S., U.K., E.U., vegetarian and vegan diets. We quantify how previous studies underestimated greenhouse gas (GHG) emissions and show that previous GHG study results for the highest tier most accurately predict average national dietary consumption.

Climate-friendly, health-promoting, and culturally acceptable diets for German adult omnivores, pescatarians, vegetarians, and vegans - a linear programming approach

OBJECTIVES

A frequently suggested approach to reduce greenhouse gas emissions (GHGEs) caused by food production is to reduce the intake of animal products, which can create nutritional deficiencies. This study aimed to identify culturally acceptable nutritional solutions for German adults that are both climate friendly and health promoting.

METHODS

Linear programming was applied to optimize the food supply for omnivores, pescatarians, vegetarians, and vegans considering nutritional adequacy, health promotion, GHGEs, affordability, and cultural acceptability by approaching German national food consumption.

RESULTS

Implementing dietary reference values and omitting meat (products) reduced the GHGEs by ≤52%. The vegan diet was alone in staying below the Intergovernmental Panel on Climate Change (IPCC) threshold of 1.6 kg carbon dioxide equivalents per person per day. The optimized omnivorous diet constrained to meet this goal maintained ≥50% of each baseline food and, on average, deviated from baseline by 36% for women and 64% for men. Butter, milk, meat products, and cheese were reduced by half for both sexes, whereas bread, bakery goods, milk, and meat were reduced mainly for men. The intake of vegetables, cereals, pulses, mushrooms, and fish increased by between 63% and 260% for the omnivores, compared with baseline. Besides the vegan dietary pattern, all optimized diets cost less than the baseline diet.

CONCLUSIONS

A linear programming approach for optimizing the German habitual diet to be healthy, affordable, and meet the IPCC GHGE threshold was possible for several dietary patterns and appears to be a feasible way forward toward including climate goals into food-based dietary guidelines.

Dietary protein consumption profiles show contrasting impacts on environmental and health indicators

Patterns of protein intake are strong characteristics of diets, and protein sources have been linked to the environmental and nutrition/health impacts of diets. However, few studies have worked on protein profiles, and most of them have focused on specific diets like vegetarian or vegan diets. Furthermore, the description of the environmental impact of diets has often been limited to greenhouse gas emissions (GHGe) and land use. This paper analyzes the alignment of environmental pressures and nutritional impacts in a diversity of representative protein profiles of a western population. Using data from a representative survey in France (INCA3, n = 1125), we identified protein profiles using hierarchical ascendant classification on protein intake (g) from main protein sources (refined grains, whole grains, dairy, eggs, ruminant meat, poultry, pork, processed meat, fish, fruits & vegetables, pulses). We assessed their diet quality using 6 dietary scores, including assessment of long-term risk for health, and associated 14 environmental pressure indicators using the Agribalyse database completed by the SHARP database for GHGe. Five protein profiles were identified according to the high contributions of ruminant meat, pork, poultry, fish, or, conversely, as low contribution from meat. The profile including the lowest protein from meat had the lowest impact on almost all environmental indicators and had the lowest long-term risk. Conversely, the profile with high protein from ruminant-based foods had the highest pressures on most environmental indicators, including GHGe. We found that the protein profile with low contribution from meat has great potential for human health and environment preservation. Shifting a large part of the population toward this profile could be an easy first step toward building a more sustainable diet.

Nutrition and its footprints: Using environmental indicators to assess the nexus between sustainability and food

Current food systems are associated with the unsustainable use of natural resources; therefore, rethinking current models is urgent and is part of a global agenda to reach sustainable development. Sustainable diets encompass health, society, economy, culture as well as the environment, in addition to considering all the stages that make up the food production chain. This study aimed to perform a review on the importance of using environmental footprints (EnF) as a way of assessing the environmental impacts of food systems. The most used EnF to assess impacts related to the food system was the carbon footprint, followed by the water footprint, and the land use footprint. These EnF usually measured the impacts mainly of the current diet and theoretical diets. Animal-source foods were the ones that most contribute to the environmental impact, with incentives to reduce consumption. However, changing dietary patterns should not be restricted to changing behavior only, but should also involve all stakeholders in the functioning of food systems. We conclude that EnF are excellent tools to evaluate and guide the adoption of more sustainable diets, and can be applied in different contexts of food systems, such as food consumption analysis, menu analysis, food waste, and inclusion of EnF information on food labels.

Five U.S. Dietary Patterns and Their Relationship to Land Use, Water Use, and Greenhouse Gas Emissions: Implications for Future Food Security

The U.S. agri-food system is a driver of climate change and other impacts. In order to achieve environmental targets that limit global mean temperature rise ≤2 °C, a shift in American dietary patterns is critical. The purpose of this study was twofold: (1) to determine the environmental impact (i.e., land use, water use, and GHG emissions) related to consumption of five U.S. dietary patterns (i.e., Current U.S., the Healthy U.S., Mediterranean, Healthy Vegetarian, and Vegan), and (2) to determine the specific impact of each food group in each dietary pattern on the three environmental indicators. This study utilized existing datasets to synthesize information related to the study's environmental indicators and food production and connected these data to the current U.S. diet and the USDA-defined diets. Results indicate that the three omnivore diets contributed the greatest to GHG emissions, land use and water use. The Vegan diet scored the lowest across all indicators, although the water required for plant-based protein nearly offset other water gains. For the omnivore diets, red meat and dairy milk contributed the most to each environmental indicator. By considering sustainability as well as health outcomes in their recommendations in the Dietary Guidelines, the USDA can have a critical role in shifting diets necessary to alter climate change trends.

Associations of daily diet-related greenhouse gas emissions with the incidence and mortality of chronic diseases: a systematic review and meta-analysis of epidemiological studies

OBJECTIVES

Although the entire process extending from food production to dietary consumption makes a large contribution to total greenhouse gas (GHG) emissions, little and inconsistent evidence exists on the epidemiological associations of daily diet-related GHG emissions with chronic disease risk or all-cause mortality. This systematic review and meta-analysis explored the observational epidemiological relationship between daily diet-related GHG emissions and health outcomes, including the risk of chronic diseases and all-cause mortality.

METHODS

Original articles published in English until May 2022 were identified by searching PubMed, Ovid-Embase, Web of Science, CINAHL, and Google Scholar. The extracted data were pooled using both fixed-effects and random-effects meta-analyses and presented as hazard and risk ratios (RRs) with 95% confidence intervals (CIs).

RESULTS

In total, 7 cohort studies (21 study arms) were included for qualitative synthesis and meta-analysis. The GHG emissions of dietary consumption showed a significant positive association with the risk of chronic disease incidence and mortality in both fixed-effects and random-effects models (fixed: RR, 1.04; 95% CI, 1.03 to 1.05; random: RR, 1.04; 95% CI, 1.02 to 1.06). This positive association was robust regardless of how daily diet-related GHG emissions were grouped. More strongly animal- based diets showed higher GHG emissions. However, there were only a few studies on specific chronic diseases, and the subgroup analysis showed insignificant results. There was no evidence of publication bias among the studies (Egger test: p=0.79).

CONCLUSIONS

A higher GHG-emission diet was found to be associated with a greater risk of all-cause mortality.

Intervention strategies to promote healthy and sustainable food choices among parents with lower and higher socioeconomic status

BACKGROUND

A global shift towards more healthy and sustainable diets is necessary for the prevention of obesity and chronic diseases, as well as for the growing pressure on our ecosystems. Given that parents are important actors in affecting dietary behaviors of their children, developing intervention strategies targeting families and their practices is promising to reach positive behavior change among children. Also, it is important to tailor these interventions to the needs of parents with different socioeconomic statuses (SES), given that health inequalities continue to grow. This study aims to investigate perspectives of lower and higher SES parents on the usability and acceptability of various innovative intervention strategies.

METHODS

Fourteen focus groups and four individual interviews (n = 78, n_lowerSES = 17; n_higherSES = 61) were conducted in Belgium. A semi-structured interview guide was used to facilitate the discussions. The interviews were recorded, transcribed, and analyzed via thematic content analysis using NVivo.

RESULTS

To encourage healthy and sustainable food choices, interventions via online food shopping platforms and nudging strategies in grocery stores were mostly cited by higher SES parents, but these were less applicable for lower SES parents as they buy less online and mainly consider the price of products. Mobile applications that provide inspiration for healthy and sustainable recipes and easily accessible shopping lists received moderate support among lower and higher SES parents. Furthermore, both lower and higher SES parents showed interest in meal boxes delivered at home, but lower SES parents have not yet tried such meal boxes because of their higher prices. Still, both groups of SES parents mentioned many advantages of these meal boxes, such as the convenience and time-saving component, as well as the cooking inspiration aspect.

CONCLUSION

Our study reveals the preferences of lower and higher SES parents for practical intervention strategies, providing insight in what features these strategies should have to be acceptable and useful. Hence, the findings can inform the development of a tailored family-based intervention strategy to improve parental food choices in favor of increased health and sustainability.

Nutritionally adequate and environmentally respectful diets are possible for different diet groups: an optimized study from the NutriNet-Santé cohort

BACKGROUND

Research has shown that vegetarian diets have a low environmental impact, but few studies have examined the environmental impacts and nutritional adequacy of these diets together, even though vegetarian diets can lead to nutritional issues.

OBJECTIVES

Our objective was to optimize and compare 6 types of diets with varying degrees of plant foods (lacto-, ovolacto-, and pescovegetarian diets and diets with low, medium, and high meat content) under nutritional constraints.

METHODS

Consumption data in 30,000 participants were derived from the French NutriNet-Santé cohort using an FFQ. Diets were optimized by a nonlinear algorithm minimizing the diet deviation while meeting multiple constraints at both the individual and population levels: nonincrease of the cost and environmental impacts (as partial ReCiPe accounting for greenhouse gas emissions, cumulative energy demand, and land occupation, distinguishing production methods: organic and conventional), under epidemiologic, nutritional (based on nutrient reference values), and acceptability (according to the diet type) constraints.

RESULTS

Optimized diets were successfully identified for each diet type, except that it was impossible to meet the EPA (20:5n-3) + DHA (22:6n-3) requirements in lacto- and ovolactovegetarians. In all cases, meat consumption was redistributed or reduced and the consumption of legumes (including soy-based products), whole grains, and vegetables were increased, whereas some food groups, such as potatoes, fruit juices, and alcoholic beverages, were entirely removed from the diets. The lower environmental impacts (as well as individual indicators) observed for vegetarians could be attained even when nutritional references were reached except for long-chain n-3 (omega-3) fatty acids.

CONCLUSIONS

A low-meat diet could be considered as a target for the general population in the context of sustainable transitions, although all diets tested can be overall nutritionally adequate (except for n-3 fatty acids) when planned appropriately.This trial was registered at clinicaltrials.gov as NCT03335644.

Changes in terms of risks/benefits of shifting diets towards healthier and more sustainable dietary models

Food production and therefore human diet are identified as important sources of environmental impact. Unhealthy and unsustainable diets with high intake of meat and low intake of plant-based products are predominant worldwide. On the other hand, a balance between health and sustainability is necessary, since diets that are environmentally sustainable could lack essential macro- and micronutrients and result in nutrient deficiencies, non-communicable diseases and malnutrition. The aim of this project was to investigate the nutritional adequacy and environmental impact of adults' diet by comparing current dietary habits and new alternative dietary scenarios. First, a systematic review was conducted following PRISMA guidelines to assess the environmental impact of current diets and sustainable dietary scenarios such as vegan, vegetarian, pescatarian, omnivorous and optimised dietary patterns worldwide. In the second part of the project, an optimisation study was conducted, based on a multi-objective optimisation approach, with the purpose of creating the optimal diet based on nutritional and environmental constraints for the adult Italian population. The dietary scenarios of the optimised models were developed in accordance with the Italian food-based dietary guidelines. Food consumption data was extracted from the INHES study and used as baseline diet. A clear evaluation of the current environmental impact because of diet and potential sustainable dietary scenarios globally is challenging. Finally, national food-based guidelines should be adjusted by suggesting healthy and sustainable dietary recommendations in line with traditional eating habits and local food availability in order the desirable dietary shifts towards sustainability to be feasible.

Dietary Environmental Footprints and Their Association with Socioeconomic Factors and Food Purchase Practices: BRAZUCA Natal Study

The analysis of dietary environmental impacts has proven to be an important tool for guiding the adoption of healthier and more sustainable diets. This study aimed to estimate the dietary carbon (CF), water (WF), and ecological (EF) footprints of residents in the city of Natal, Brazil; the study also aimed to verify their association with socioeconomic factors and food purchase practices. This is a cross-sectional study that used dietary data from 411 adults and elderlies, which was collected via a questionnaire that applied to the respondents. The results showed that the dietary CF was 1901.88 g CO2 eq/day/1000 kcal, the WF was 1834.03 L/day/1000 kcal, and the EF was 14.29 m2/day/1000 kcal. The highest environmental footprint values showed an association (p ≤ 0.05) with the factors of male sex, white ethnicity, and higher income and schooling, whereas the lowest environmental footprint values were associated with social vulnerability variables such as female sex, non-white ethnicity, and lower income and schooling (p ≤ 0.05). Moreover, people with lower environmental footprints consumed less fast food, had fewer meals at snack bars, and used food delivery services less often than those with higher footprints. The foods that most contributed to the CFs and WFs were beef and chicken, while fish and beef contribute the most to the EFs. The data in the present study show that a diet with a lower environmental impact is not always equal to a sustainable diet. This relationship is paradoxical and relates to food justice, as people with lower environmental footprint values are the same ones with worse socioeconomic conditions. In this sense, is it essential to consider the influence of the social context when assessing dietary environmental impacts and when assessing actions that promote healthier and more sustainable diets.

Environmental impacts and diet quality of popular diet models compared to Turkey's national nutrition guidelines

AIMS

This study aimed to compare the environmental impacts and diet qualities of popular diet models with the recommendations of the Turkish national dietary guidelines.

METHODS

Seven-day isocaloric (8368 kJ) diet models were created taking into account the Mediterranean, Atkins (20/40/100), Ornish, Zone diets, and Turkey Dietary Guidelines-2015 recommendations with different food and nutrient contents. Water footprints were evaluated using the global water footprint standards. Greenhouse gas emissions were evaluated using carbon footprint factors compiled as a result of meta-analyses of life cycle analysis studies in the literature. In addition, the quality of diets was evaluated with the Diet Quality Index-International.

RESULTS

Atkins20 diet model had the most harmful environmental impact (greenhouse gas emissions 8.74 kg CO₂ -eq/per/day and total water footprint 7731 L/per/day), whereas Ornish and Mediterranean diet models (greenhouse gas emissions 2.2/3.07 kg CO₂ -eq/per/day and total water footprints 3184/3675 L/per/day, respectively) had less harmful environmental impact. The highest Diet Quality Index-International score was in the Ornish diet model while the lowest Diet Quality Index-International was in the Atkins20 diet model.

CONCLUSION

Ornish and Mediterranean diet models had less harmful environmental impacts, which contributed to sustainable nutrition. The importance of diet quality and environmental impacts should be kept in mind when evaluating diet models to ensure sustainable nutrition.

Environmental footprints of food consumption: Protocol for a systematic literature review

Environmental footprints are indicators that can be used to estimate the impacts of diet on the environment. Since contemporary dietary practices are related to negative environmental impacts, this paper aims to describe a systematic review protocol to investigate the environmental footprints of food consumption by adults and elderly individuals worldwide. This protocol was developed based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Search strategies and records of evidence searched in previously defined electronic databases will be defined. Original, population-based articles investigating the environmental footprints of food consumption by adults and the elderly will be included. Two independent reviewers will conduct the study selection and data extraction steps. Critical appraisal of the included studies will be based on the Newcastle-Ottawa Scale. For data synthesis, a narrative synthesis and, if possible, also a meta-analysis will be performed. The systematic review produced from this protocol will provide evidence for data synthesis of the environmental impact through environmental footprints of food consumption of the adult and elderly population from different territories and the footprint assessment tools used around the world. Therefore, it is a gap that needs to be filled because knowing these impacts will be important to inform the development of public policies that encourage healthy and sustainable food in the face of climate and epidemiological changes. PROSPERO registration number: CRD42021281488.

Food purchase behaviour in a Finnish population: patterns, carbon footprints and expenditures

OBJECTIVE

To identify food purchase patterns and to assess their carbon footprint and expenditure.

DESIGN

Cross-sectional.

SETTING

Purchase patterns were identified by factor analysis from the annual purchases of 3435 product groups. The associations between purchase patterns and the total purchases' carbon footprints (based on life-cycle assessment) and expenditure were analysed using linear regression and adjusted for nutritional energy content of the purchases.

PARTICIPANTS

Loyalty card holders (n 22 860) of the largest food retailer in Finland.

RESULTS

Eight patterns explained 55 % of the variation in food purchases. The Animal-based pattern made the greatest contribution to the annual carbon footprint, followed by the Easy-cooking, and Ready-to-eat patterns. High-energy, Traditional and Plant-based patterns made the smallest contribution to the carbon footprint of the purchases. Animal-based, Ready-to-eat, Plant-based and High-energy patterns made the greatest contribution, whereas the Traditional and Easy-cooking patterns made the smallest contribution to food expenditure. Carbon footprint per euros spent increased with stronger adherence to the Traditional, Animal-based and Easy-cooking patterns.

CONCLUSIONS

The Animal-based, Ready-to-eat and High-energy patterns were associated with relatively high expenditure on food, suggesting no economic barrier to a potential shift towards a plant-based diet for consumers adherent to those patterns. Strong adherence to the Traditional pattern resulted in a low energy-adjusted carbon footprint but high carbon footprint per euro. This suggests a preference for cheap nutritional energy rather than environment-conscious purchase behaviour. Whether a shift towards a plant-based pattern would be affordable for those with more traditional and cheaper purchase patterns requires more research.

Nutritional Composition and Environmental Impact of Meals Selected in Workplace Canteens before and after an Intervention Promoting the Adherence to the Mediterranean Diet

Enhancing healthy and sustainable food systems is one of the key goals of the current European Commission policy. In this light, the creation of a food environment where people are properly informed about the healthiness and sustainability of food choices is essential. This study aimed to evaluate the nutritional profile and the environmental impact of meals consumed in a workplace canteen in Italy in the presence of a nudge (i.e., the Double Pyramid logo) combined with a web-based application promoting the Mediterranean Diet. Energy and nutrient contents and the carbon, water, and ecological footprints of 29,776 meals were compared across three subsequent periods (from June to April) through one-way ANOVA. Although the choice of dishes labelled with the Double Pyramid logo was comparable across periods, the selection of fish- and plant-based dishes increased from +2% (fish, vegetables) up to +17% (whole-grain cereals), with a concurrent reduction of meat-based options (−2%). Although the consumption of healthy items increased (p < 0.001), they were not added as a replacement for alternative options, leading to a higher content in energy (p < 0.001) and nutrients (p < 0.001) and worse environmental footprints, contrarily to what was observed when data were adjusted for energy. The intervention significantly improved food choices; however, as the higher selection of desired dishes was not adequately compensated for, it was not fully effective.

The importance of protein variety in a higher quality and lower environmental impact dietary pattern

OBJECTIVE

Eating a variety of nutritious foods is fundamental to good nutrition. However, this principle is challenged when recommendations seeking to improve the environmental sustainability of diets call for avoidance of foods considered to have a higher environmental footprint, such as animal-sourced foods. Our objective was to assess the implications for nutritional adequacy of protein choice across Australian adult diets preselected as having higher quality and lower environmental impact scores.

DESIGN

Each individual diet was assessed for variety of food choice within the 'Fresh meat and alternatives' food group defined in the Australian Dietary Guidelines, which includes protein-rich foods such as eggs, nuts, tofu and legumes in addition to animal meats. Diets were grouped according to variety score and whether they included only animal meats, only alternatives or a variety of meat and alternatives. Nutrient content was assessed relative to estimated average requirements (EAR).

SETTING

Australia.

PARTICIPANTS

1700 adults participating in the Australian Health Survey.

RESULTS

For diets with higher diet quality and lower environmental impact, the likelihood of achieving nutrient EAR significantly increased as variety of food choice in the 'Fresh meat and alternatives' food group increased (P < 0·001). Variety score and number of serves were also correlated (r = 0·52, P < 0·001) which is relevant since most diets did not meet the recommended minimum number of serves for this food group.

CONCLUSIONS

Greater variety within the 'Fresh meat and alternatives' food group is beneficial to meeting EAR and lower environmental impact diets can include three or more selections including foods of animal origin.

Association between adherence to the EAT-Lancet diet and risk of cancer and cardiovascular outcomes in the prospective NutriNet-Santé cohort

BACKGROUND

The EAT-Lancet commission proposed, in 2019, a planetary, healthy, and universal dietary pattern. However, this diet has rarely been studied in relation to various health outcomes.

OBJECTIVES

We aimed to prospectively estimate the association between the EAT-Lancet diet and cancer and cardiovascular disease (CVD) risk.

METHODS

The study was conducted in participants of the NutriNet-Santé cohort (2009-2021). The endpoints were the incident outcomes (cancer and CVDs and mortality from these diseases), combined and separately. Adherence to the EAT-Lancet diet was estimated using the EAT-Lancet Diet Index (ELD-I) modeled as quintiles (Qs). Multivariable Cox proportional hazard models were used to estimate HRs and 95% CIs, adjusted for potential confounders and moderators.

RESULTS

A total of 62,382 subjects were included; 2475 cases of cancer and 786 cases of cardiovascular events occurred during a median follow-up of 8.1 y. The sample was 76% female, the mean ± SD age at inclusion was 51.0 ± 10.2 y. The ELD-I ranged from -162 to 332 points with a mean ± SD score of 45.4 ± 25.6 points. In multivariable models, no significant association between the EAT-Lancet diet and the risk of cancer and CVD combined, and separately, was observed. Alcohol consumption was an effect modifier of the association. A significant association was observed among low drinkers (HRQ5vs.Q1: 0.86; 95% CI: 0.73, 1.02; P-trend = 0.02). A higher ELD-I was significantly associated with a lower risk of overall cancer only among females (HRQ5vs.Q1: 0.89; 95% CI: 0.75, 1.05; P-trend = 0.03). Both associations were largely attenuated by BMI.

CONCLUSIONS

Contrary to our hypothesis, our results documented significant associations between adherence to the EAT-Lancet diet and incidence of cancer only in some subgroups, and no association with CVD.This trial was registered at clinicaltrials.gov as NCT03335644.

Consumer Preference Segments for Plant-Based Foods: The Role of Product Category

A survey of willingness to consume (WTC) 5 types of plant-based (PB) food was conducted in USA, Australia, Singapore and India (n = 2494). In addition to WTC, emotional, conceptual and situational use characterizations were obtained. Results showed a number of distinct clusters of consumers with different patterns of WTC for PB foods within different food categories. A large group of consumers did not discriminate among PB foods across the various food categories. Six smaller, but distinct clusters of consumers had specific patterns of WTC across the examined food categories. In general, PB Milk and, to a much lesser extent, PB Cheese had highest WTC ratings. PB Fish had the lowest WTC, and two PB meat products had intermediate WTC. Emotional, conceptual and situational use characterizations exerted significant lifts/penalties on WTC. No penalty or lifts were imparted on WTC by the situational use of 'moving my diet in a sustainable direction', whereas uses related to 'when I want something I like' and 'when I want something healthy' generally imparted WTC lifts across clusters and food categories. The importance of this research for the study of PB foods is its demonstration that consumers are not monolithic in their willingness to consume these foods and that WTC is often a function of the food category of the PB food.

The Need for Consumer-Focused Household Food Waste Reduction Policies Using Dietary Patterns and Socioeconomic Status as Predictors: A Study on Wheat Bread Waste in Shiraz, Iran

Current household food waste (HFW) reduction plans usually focus on raising consumer awareness, which is essential but insufficient because HFW is predominantly attributed to unconscious behavioral factors that vary across consumer groups. Therefore, identifying such factors is crucial for predicting HFW levels and establishing effective plans. This study explored the role of dietary patterns (DP) and socioeconomic status (SES) as predictors of HBW using linear and non-linear regression models. Questionnaire interviews were performed in 419 households in Shiraz during 2019. A multilayer sampling procedure including stratification, clustering, and systematic sampling was used. Three main DPs, i.e., unhealthy, Mediterranean, and traditional, were identified using a food frequency questionnaire. Results indicated that a one-unit rise in the household’s unhealthy DP score was associated with an average increase in HBW of 0.40%. Similarly, a one-unit increase in the unhealthy DP score and the SES score increased the relative likelihood of bread waste occurrence by 25.6% and 14.5%, respectively. The comparison of findings revealed inconsistencies in HFW data, and therefore the necessity of studying HFW links to factors such as diet and SES. Further investigations that explore HFW associations with household characteristics and behavioral factors will help establish contextual and effective consumer-focused plans.

Exploring the environment-nutrition-obesity effects associated with food consumption in different groups in China

Unsustainable diet is one of the main reasons for the nutrition-health-environment trilemma. However, information on environment-nutrition-obesity effects associated with food consumption is still limited. This study analyzes these diet-related impacts of different groups classified by various socio-economic attributes: location, gender, age, income, education, and occupation. We applied the samples in China Health and Nutrition Survey and divided them into advantaged group and dis-advantaged group according to the probability of access to more nutritious food. Results show that the advantaged groups had higher and more rapidly increasing dietary and nutrition quality than their counterpart during 1997-2011. On the contrary, the non-advantaged group' body mass index increased faster. Meanwhile, the high-income group as well as government and professional & technological workers have passed the criterion for overweight. The environmental footprints, i.e., nitrogen, phosphorus, carbon, and water footprints, of high-income group were higher 89%, 70%, 98%, and 41% than low-income group, respectively. Notably, food consumption sustainability of each group has declined, and the non-advantaged groups' is much more sustainable. We concluded that inequality existed and tends to expand in food consumption and its related impacts of different socio-economic groups. A reformed responsibility allocation system is needed during dietary transition for better environmental management. Strategies to improve dietary quality for advantaged group focus on improving the types of high-quality protein foods, such as milk and seafood, while the non-advantaged group can choose to increase the types of high-quality but relatively cheap foods like vegetables and fruits considering the availability and living cost.