Evaluating the environmental impact of various dietary patterns combined with different food production systems

Regional food consumption in Italy, a life cycle analysis

Urbanization and globalization have led to an increasing concern and focus on the sustainability of the food sector, particularly in discussing the composition of consumers' diets. This study examines Italian consumption habits, categorizing them into four macro-geographical areas (North-West, North-East, Center, South, and Islands), utilizing public data obtained from surveys including 3323 individuals, and assesses their environmental impacts through the application of the Life Cycle Assessment methodology. The findings unveil distinct dietary patterns across Italian macro-regions, indicative of cultural disparities, and present avenues for promoting environmentally sustainable dietary choices. The study identifies meat consumption as the primary environmental concern across all macro-regions, with fish emerging as a secondary contributor to particulate matter formation. Pork and poultry exhibit notable impacts within toxicity-related categories. Additionally, the research underscores challenges in data collection, notably the absence of a site-specific Italian database, and underscores the necessity for more recent consumption data to accurately capture contemporary Italian dietary habits. Finally, the study demonstrates that addressing the issue from a macro-regional perspective allows for more targeted and dedicated cultural interventions.

Mathematical analysis and control optimization of soluble and insoluble water pollutants dispersion

One of the major and abundant environmental elements is water, which life existence on earth is depending on. However, degradation of water quality arising from natural occurrences due to anthropogenic that resulted in eutrophication needs to be guided. Indiscriminate harmful waste discharge and dispersion into the water bodies leads to water pollution. As such, constant management and monitoring of water resources for an enhanced quality and quantity is essential. Therefore, this study employed a coupled derivative mathematical model to investigate soluble and insoluble water pollutants. The insoluble pollutants are converted to soluble pollutants through an applied control or treatment. To optimize the water quality, parametric sensitivities in relation to reproduction number are examined. From the computational analysis carried out, it was revealed that treatment still remains the only remedy for safe water.

Green hospitals: Mitigating water footprint and greenhouse gas emissions through sustainable menu planning in Turkish state university hospitals

Considering the importance of sustainable nutrition, it is important that hospitals' meal menus are planned to ensure the lowest possible environmental footprint. In this study, we aimed to evaluate the environmental effects of hospital menus and the changes that may occur when these menus are planned according to the Turkey Dietary Guidelines and Mediterranean diet recommendations. In this context, first, the yearly environmental footprints of the standard meal menus of the state university hospitals in Turkey (n = 42), including water footprint (WF) and greenhouse gas emission (GHGE) values, were determined. Second, changes in the environmental footprint as a result of arranging the standard meal menus of state university hospitals according to the Turkey Dietary Guidelines and Mediterranean nutritional models were evaluated. It was determined that the average WF and GHGE values of hospital menus were 137,280 ± 18537.2 L/month and 140.0 ± 18.4 kg CO2-eq/month, respectively. Adjusting state university hospitals' standard meal menus according to Turkey Dietary Guidelines and Mediterranean nutritional models reduced WF by 24.8% to 103206.7 L/month and 37.8% to 85420.5 L/month, and GHGEs by 31.7% to 95.5 kg CO2-eq/month and 49% to 71.3 kg CO2-eq/month, respectively. In addition, it was determined that hospital meal menus planned according to the Turkey Dietary Guidelines and the Mediterranean nutritional model contained lower saturated fat and cholesterol and higher dietary fiber. In conclusion, planning hospital menus according to the Turkey Dietary Guidelines and Mediterranean nutritional recommendations can reduce the environmental footprint of hospital food services.

Plant-based and planetary-health diets, environmental burden, and risk of mortality: a prospective cohort study of middle-aged and older adults in China

BACKGROUND

Plant-based diets (PBDs) and planetary-health diets (PHDs) are recommended for their potential health and environmental benefits, but population-based evidence in diverse cultures is scarce.

METHODS

We included 9364 adults aged 45 years and older (52·3% female, 47·7% male) from the open cohort of the China Health and Nutrition Survey. Dietary intake was assessed using 3-day 24 h dietary recalls combined with weighing methods from 1997 to 2011, and mortality was documented from 1997 to 2015. We calculated the overall PBD index (PDI), healthful PBD index (hPDI), and unhealthful PBD index (uPDI; ranges 18-90), and the PHD score (range 0-140). We also estimated the related greenhouse gas emissions, land appropriation, and total water footprint and examined their associations with mortality.

FINDINGS

PBD indices were inversely related to greenhouse gas emissions, land appropriation, and total water footprint, whereas higher PHD score was related to higher environmental burdens (p<0·0001). During follow-up (mean 9·2 years), 792 (8·5%) death cases were documented. PDI (HR 1·08 [95% CI 0·88-1·32]) and hPDI (0·98 [0·80-1·21]) were not significantly associated with mortality, whereas higher uPDI was related to a higher mortality risk (1·55 [1·26-1·91]). In contrast, higher PHD score was associated with lower mortality risk (0·79 [0·63-0·99]).

INTERPRETATION

The PBDs showed environmental benefits, but are not necessarily associated with lower mortality risk. The PHD, developed mainly in western populations, was related to lower mortality risk but higher environmental burdens in the Chinese population.

FUNDING

Fundamental Research Funds for the Central Universities, Zhejiang University Global Partnership Fund, and National Natural Science Foundation of China.

Psychological differences and similarities between vegans, prospective vegans, and vegetarians. Motivation, knowledge, vegan literacy - and cheese

Introduction

Although vegan and vegetarian diets and lifestyles differ significantly from each other, among other things, notably in their respective consequences regarding animal welfare and their ecological impact, vegans and vegetarians are often grouped together and usually compared to omnivores in psychological research. Considering that vegans and vegetarians often share similar motives for their lifestyle choices, namely animal and environmental issues, the question arises why similar motives lead to different conclusions and correspondingly different behaviors, most notably, of course, that vegetarians consume animal-derived foods such as cheese or milk while vegans do not consume animal-derived products (e.g., food, cosmetic products). This is why this study explored the psychological differences between vegans, vegetarians, and prospective vegans - the latter group being located in an intermediate, transitionary position. Focusing on the motivational, affective and cognitive components of dietary transition and participants' adherence to eating patterns, reasons for said patterns, possible hinderances to becoming vegan, the role of participants' social environments, and the impact of various misconceptions regarding the feasibility of a vegan diet in everyday life were all explored.

Methods

An observational study was conducted via online questionnaire (1420 participants).

Results

Significant differences were found between vegans, prospective vegans, and vegetarians, especially concerning their knowledge of issues pertaining to their respective lifestyles.

Discussion

The critical role of knowledge is invoked as an explanation as to why vegans and vegetarians display different behaviors although they share a similar motivation. Thus, in this study the concept of vegan literacy is introduced. Additionally, the distinctive role of cheese is explored, discussing possible indications of its potentially addictive nature and, consequently, the importance of cheese as a hindering factor for pursuing a vegan diet.

Relationship between adherence to the Mediterranean diet, sustainable and healthy eating behaviors, and climate change awareness: A cross-sectional study from Turkey

OBJECTIVES

This study aimed to evaluate the relationship between adherence to the Mediterranean diet, sustainable and healthy eating behaviors, and climate change awareness in adults.

METHODS

This descriptive and cross-sectional study was conducted with 1797 adults ages 19-65 y. Demographic characteristics, anthropometric measurements, adherence to the Mediterranean diet, sustainable and healthy eating behaviors, and climate change awareness were ascertained through a questionnaire.

RESULTS

The mean age of the individuals was 27.5 ± 11.76 y, and 50.5% of the participants were adherent to the Mediterranean diet. A statistically significant difference was found between individuals who did and did not adhere to the Mediterranean diet in terms of age, income status, total score and subscores on the Sustainable and Healthy Eating Behaviors Scale, and subscores for information on climate change causes (P < 0.05). A statistically significant positive correlation was found between the Mediterranean Diet Adherence Scale (MEDAS) total score, the Sustainable and Healthy Eating Behaviors Scale total score and subscores, and the Climate Change Awareness Scale total score and subscores (P < 0.05). It was determined that sex, education level, and income status affected the Climate Change Awareness Scale total score (P < 0.05). It was determined that age, income status, the Sustainable and Healthy Eating Behaviors Scale total score, and the Climate Change Awareness Scale total score affected the MEDAS total score (P < 0.05). Also, it was determined that age, sex, education level, MEDAS total score, and Climate Change Awareness Scale total score affected the Sustainable and Healthy Eating Behaviors Scale total score (P < 0.05).

CONCLUSIONS

This study showed a significant effect of climate change awareness on sustainable and healthy eating behaviors and adherence to the Mediterranean diet.

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.

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.

Environmental Impact of Two Plant-Based, Isocaloric and Isoproteic Diets: The Vegan Diet vs. the Mediterranean Diet

Food consumption is one of the major causes of climate change, resource depletion, loss of biodiversity, and other kinds of environmental impact by modern households. According to evidence, a global change in dietary habits could be the single most effective and rapid intervention to reduce anthropic pressure on the planet, especially with respect to climate change. Our study applied Life Cycle Assessment (LCA) to investigate the total environmental impact of two plant-based diets: the Mediterranean and the Vegan diets, according to relevant Italian nutritional recommendations. The two diets share the same macronutrient rates and cover all the nutritional recommendations. Calculations were made on the basis of a theoretical one-week 2000 kcal/day diet. According to our calculations, the Vegan diet showed about 44% less total environmental impact when compared to the Mediterranean diet, despite the fact that the content of animal products of the latter was low (with 10.6% of the total diet calories). This result clearly supports the concept that meat and dairy consumption plays a critical role, above all, in terms of damage to human health and ecosystems. Our study supports the thesis that even a minimal-to-moderate content of animal foods has a consistent impact on the environmental footprint of a diet, and their reduction can elicit significant ecological benefits.

Legumes or Meat? The Effectiveness of Recommendation Messages towards a Plant-Based Diet Depends on People's Identification with Flexitarians

In the present research, we analyzed how to promote a plant-based diet by involving 428 volunteers in a 2-week mobile app intervention. We compared messages promoting the addition of legumes versus messages promoting the replacement of meat with legumes. Messages were either combined or not combined with dynamic norms (i.e., information that more and more people are enacting the behavior). We compared these messages with a control condition (i.e., no message intervention) and we also analyzed the moderation effect of receivers' identification with flexitarians (i.e., people who occasionally eat animal products) and attitudes towards them. In the short term, addition messages increased legume consumption more than replacement messages, especially in people with a negative evaluation of flexitarians and low identification with them. In the long term, increased legume consumption was recorded only when addition messages were combined with dynamic norms. As for meat consumption, the replacement messages were more effective in reducing it in the short term than in the long term, especially in people with positive attitudes towards flexitarians. However, replacement messages combined with dynamic norms were more effective in the long term than in the short term. These results advance our comprehension of how to tailor dietary messages.

Animal- and Plant-Based Protein Sources: A Scoping Review of Human Health Outcomes and Environmental Impact

Dietary proteins are indispensable to human nutrition. In addition to their tissue-building function, they affect body composition and regulate various metabolic pathways, as well as satiety and immune system activity. Protein use can be examined from a quantitative or qualitative viewpoint. In this scoping review, we compare animal- and plant-based protein sources in terms of their effects on human health and the environment. We conclude that the consumption of vegetable protein sources is associated with better health outcomes overall (namely, on the cardiovascular system) than animal-based product use. The healthier outcomes of vegetable protein sources dovetail with their lower environmental impact, which must be considered when designing an optimal diet. Indeed, the health of the planet cannot be disjointed from the health of the human being. Future research will clarify the mechanisms of action underlying the health effects of plant-based protein sources when compared with animal sources, fostering better agronomic practices and influencing public health in a direction that will benefit both the planet and its inhabitants.

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.

Pulse protein processing: The effect of processing choices and enzymatic hydrolysis on ingredient functionality

Plant-based protein ingredients are an emerging solution to the environmental and health issues associated with animal-based proteins. Pulses have become a promising source of these plant-based ingredients. In order to produce functional proteins from pulse grains, extensive processing must be conducted to extract their proteins. These processing steps have consequential effects on the composition and structure of the resulting proteins which may modify their functional properties. This study reviews the most prominent options for each unit operation of pulse protein processing such as extraction, isolation, and drying. It also emphasizes the benefits and drawbacks of such methods and their effects on the pulse protein functionality. Furthermore, enzymatic hydrolysis is discussed as an optional processing step that is thought to counteract loss of functionality associated with pulse protein isolation. However, review of enzymatic hydrolysis literature reveals methodological issues in which insoluble and nonfunctional fractions of pulse protein hydrolysates are removed before analysis. This literature may draw into question the validity of the conventional wisdom that enzymatic hydrolysis is always beneficial to protein functionality.

Functional, thermal and structural properties of fractionated protein from waste banana peel

Defatted banana peel powder was fractionated using the Osborne method to extract albumin, globulin, prolamin, and glutelin for physicochemical and functional characterization. The total recovery of protein was ∼89.76%. Albumin was the dominant one in terms of yield (62.4%) and protein content (65.15%) among all the fractions. The mean diameter of albumin (635.05 µm) and glutelin (642.62 µm) were significantly smaller than globulin (726.81 µm) and prolamin (986.45 µm). The highest water (1.86 ± 0.12 g/g), oil (1.97 ± 0.12 g/g) holding capacity, and emulsion capacity (59.27 ± 1.25%) were found for the albumin fraction. In contrast, the glutelin fraction showed the highest foaming capacity (19.13 ± 0.41%) and dispersibility (951.55 ± 3.83 g/kg). The denaturation temperature of protein fractions was found in the range of 30.31-82.08 °C. FTIR confirmed low carbohydrates and protein richness of albumin fraction. XRD revealed the crystalline nature of albumin (65%) and the amorphous nature of other fractions (41-45%). The morphology of all fractions was different, which influenced the functional characteristics.

Dietary Patterns at the Individual Level through a Nutritional and Environmental Approach: The Case Study of a School Canteen

The public catering sector has important responsibilities in seeking a change toward more sustainable choices for many aspects related to the environmental impacts of their services. The environmental impact of production processes can be studied through life cycle assessment (LCA), which allows a greater awareness of choices and has rarely been applied to catering. In this work, we studied the impacts of two dishes (braised meat and cauliflower meatballs) in a school canteen, their impacts were studied using the daily energy requirement (expressed in kcal) as a functional unit. Global warming potential (GWP) and nonrenewable energy (NRE) were calculated starting from the supply of raw materials up to distribution. Electricity and the act of cooking the meatballs accounted for more than 60% of the measured impact in terms of GWP, whereas, less markedly, they dominated in terms of nonrenewable energy used. In the case of braised meat, the total impact was, however, attributable to the life cycle of the meat (between 60% and 76%) and the consumption of electricity (between 19% and 27%), whereas for all other factors, the contribution was never particularly high. Additionally, a discussion on the correct functional unit to be used proposed the environmental impact of different recipes as an additional criterion for nutritionists during the composition of the menu. An integrated system appears important for changing policies and behaviors and the application of LCA can be a tool capable of contributing to the construction of a holistic instrument of sustainability.

Advantages and limitations of the methodological approaches used to study dietary shifts towards improved nutrition and sustainability

Acting on diet is one of the changes required - in combination with actions on food production, transformation, and waste - to address the challenges of reducing the environmental impact of our food systems and eliminating all forms of malnutrition. The number of studies exploring how to move towards a more sustainable diet has exploded over the past decades, but there is a need to facilitate their understanding and use by policy makers and all other stakeholders possibly influencing diet sustainability. The aim of the present article is to propose a categorization of studies into 4 approaches, based on the type of methodology used to explore diet sustainability, and to highlight the principles, advantages, and limitations of each approach in order to help study users in their interpretation. The 4 approaches are: assessment of sustainability characteristics of hypothetical diets (approach 1) or existing diets (approach 2), identification of existing "positive deviants" (approach 3), and design of more sustainable diets with constrained optimization (approach 4). Specificities and key findings drawn from each approach are described, and challenges for future studies are discussed.

Quality and Shelf-Life Stability of Pork Meat Fillets Packaged in Multilayer Polylactide Films

In the present study, the effectiveness of a multilayer film of polylactide (PLA), fully bio-based and compostable, was ascertained to develop a novel sustainable packaging solution for the preservation of fresh pork meat. To this end, the multilayer PLA films were first characterized in terms of their thermal characteristics, structure, mechanical performance, permeance to water and aroma vapors and oxygen, and optical properties and, for the first time, compared with two commercial high-barrier multilayer packaging films. Thereafter, the multilayers were thermosealed to package fillets of fresh pork meat and the physicochemical changes, lipid oxidation levels, and microbiological counts were monitored in the food samples during storage under refrigeration conditions. Results showed that the meat fillets packaged in PLA developed a redder color and showed certain indications of dehydration and oxidation, being more noticeably after 11 days of storage, due to the higher water vapor and oxygen permeance values of the biopolymer multilayer. However, the pH changes and bacterial growth in the cold-stored fresh pork meat samples were minimal and very similar in the three tested multilayer films, successfully accomplishing the requirements of the food quality and safety standards at the end of storage.

Large-Scale Microanalysis of U.S. Household Food Carbon Footprints and Reduction Potentials

Promoting sustainable food consumption is critical to meet the United Nation's Sustainable Development Goals. The existing research using average diets and the individual one-day diet recall data to obtain insights into food carbon footprints (CFs) may neglect the diverse food purchasing patterns in different households (HHs). In this paper, we analyzed detailed grocery shopping records of 57,578 U.S. HHs to evaluate the associated food CFs. The cradle-to-farm-gate CFs of 83 food items were calculated using a process-based life cycle assessment model adapted to the U.S. condition. Using the CF of a healthy and sustainable diet as the benchmark, we quantified the CF reduction potentials for each HH. Our results suggest three key strategies to reduce HH food CFs: (1) lowering the over-purchasing in small (one- or two-person) HHs can achieve two-thirds of the recognized carbon emission reduction potentials; (2) reducing the intake of snacks, ready-made food, and drinks leads to as much as, if not more, carbon emission reduction than changing diets; and (3) more attention needs to be paid to reduce the carbon intensity of food items with large purchased volume.

Greenhouse gases emissions from the diet and risk of death and chronic diseases in the EPIC-Spain cohort

BACKGROUND

Evidence from the scientific literature shows a significant variation in greenhouse gas (GHG) emissions from the diet, according to the type of food consumed. We aim to analyze the relationship between the daily dietary GHG emissions according to red meat, fruit and vegetables consumption and their relationship with risk of total mortality, and incident risk of chronic diseases.

METHODS

We examined data on the EPIC-Spain prospective study, with a sample of 40 621 participants. Dietary GHG emission values were calculated for 57 food items of the EPIC study using mean emission data from a systematic review of 369 published studies.

RESULTS

Dietary GHG emissions (kgCO2eq/day), per 2000 kcal, were 4.7 times higher in those with high red-meat consumption (>140 g/day) than those with low consumption (<70 g/day). The average dietary GHG emissions were similar in males and females, but it was significantly higher in youngest people and in those individuals with lower educational level, as well as for northern EPIC centers of Spain. We found a significant association with the risk of mortality comparing the third vs. the first tertile of dietary GHG emissions [hazard ratio (HR) 1.095; 95% confidence interval (CI) 1.007-1.19; trend test 0.037]. Risk of coronary heart disease (HR 1.26; 95% CI 1.08-1.48; trend test 0.003) and risk of type 2 diabetes (HR 1.24; 95% CI 1.11-1.38; trend test 0.002) showed significant association as well.

CONCLUSIONS

Decreasing red-meat consumption would lead to reduce GHG emissions from diet and would reduce risk of mortality, coronary heart disease and type 2 diabetes.

Default Vegetarianism and Veganism

This paper describes a pair of dietary practices I label default vegetarianism and default veganism. The basic idea is that one adopts a default of adhering to vegetarian and vegan diets, with periodic exceptions. While I do not exhaustively defend either of these dietary practices as morally required, I do suggest that they are more promising than other dietary practices that are normally discussed like strict veganism and vegetarianism. For they may do a better job of striking a balance between normative concerns about contemporary farming practices and competing considerations of life. Additionally, I argue that framing discussions in terms of defaults is useful for various reasons: it helps organize agreements and disagreements, it more accurately reflects the way people conceptualize their dietary practices, and it presents a more dialectically effective view.

Effect of food on orally-ingested titanium dioxide and zinc oxide nanoparticle behaviors in simulated digestive tract

Nanomaterials have been widely utilized in human daily life. The interaction between nanoparticles (NPs) and food matrices through oral ingestion is important for fate and potential toxicity of NPs. In this study, the interaction between NPs (i.e., titanium dioxide (TiO₂) and zinc oxide (ZnO)) and food matrices (namely sucrose, protein powder, and corn oil) was investigated by use of an in vitro physiological model. Measurement using asymmetrical flow field-flow fractionation (AF₄) showed that particle size of TiO₂ NPs in saliva fluid decreased from 102 ± 6.21 nm (control) to 69.2 ± 6.90 and 81.9 ± 4.30 nm in protein powder and corn oil. Similar trend was also observed for ZnO. Compared with gastric fluid, micelles formed by corn oil in intestinal fluid further dispersed NPs, as indicated by approximately 11.1% and 13.2% decrease in particle size of TiO₂ and ZnO NPs, respectively. Characterization of TEM, FTIR and AFM showed that a layer of biological corona was attached on surface of NPs in protein and oil. The XPS demonstrated that oil bound with NPs through forming covalent bonds, while protein bound with NPs through van der Waals force and electrostatic force for TiO₂ and ZnO NPs, respectively. The result here demonstrated the importance of considering food effect when investigating the morphology and behavior of NPs after oral ingestion. This understanding was valuable in assessment of environmental fate and biological effects of NPs.

Vegan Diet Health Benefits in Metabolic Syndrome

Plant-based diets (PBDs) are increasingly consumed by the Italian population and around the world. In particular, among PBDs, the vegan diet is a food pattern characterized by the exclusion of all animal-origin foods. What drives people to adopt this model are mainly ethical, health and environmental reasons. A vegan diet, if well-balanced and varied, can help in achieving and maintaining an optimal state of health. However, this nutritional approach, if not well-balanced, can cause deficiencies in proteins, ω-3 fatty acids, iron, vitamin D and calcium, zinc, iodine and, above all, vitamin B12. Oral food supplements especially fortified foods are recommended in these cases to restore the nutritional deficiencies. A vegan diet generally reduces the risk of developing chronic non-communicable degenerative diseases, such as metabolic syndrome (MetS) and, in addition, requires fewer natural resources for food production than an omnivorous diet. The aim of this review is to analyze the possible impact of the vegan diet on MetS onset and its treatment.

Development and testing of the Sustainable Nutrition Environment Measures Survey for retail stores in Ontario

OBJECTIVE

To develop and test a tool to assess the price and availability of low-carbon footprint and nutritionally balanced dietary patterns in retail food environments in Ontario, Canada.

DESIGN

Availability and price of selected food from discount and regular grocery stores (n 23) in urban/rural areas of northern/southern Ontario were assessed with the Sustainable Nutrition Environment Measures Survey in 2017.

SETTING

Ontario, Canada.

RESULTS

Inter-rater reliability was high for price (intra-class correlation coefficients = 0·819) and for availability (Cohen's κ = 0·993). The tool showed 78 % of the selected food items were available in all stores. Overall, price differences were small between urban and rural locations, and northern and southern Ontario. The greatest price difference was between discount and regular stores.

CONCLUSIONS

The tool showed excellent inter-rater agreement. Researchers and public health dietitians can use this tool for research, practice and policy to link consumer-level health outcomes to the retail environment.

"I'll try the veggie burger": Increasing purchases of sustainable foods with information about sustainability and taste

Food production--especially raising animals for meat--has a massive negative impact on the environment and contributes to global warming. To address this, we investigated whether information about food sustainability would increase purchases of sustainable foods by patrons of university cafés. In Study 1, patrons were randomly assigned either to see a menu that had sustainability labels indicating the degree of environmental impact of each item, or to see a menu without labels. Women who saw the labels were significantly more likely to purchase sustainable foods, whereas men were not influenced by the labels. In Study 2 we targeted one sustainable menu item (a veggie burger) and, in a 2 (sustainability) x 2 (taste) design, varied whether patrons learned that the veggie burger was especially sustainable or especially tasty. Women were significantly more likely to purchase the veggie burger if they learned it was sustainable or tasty, but again, the manipulations had no effect on men. We discuss why women are more likely to change their food choices to eat more sustainably than are men.

Influence of the Socio-Cultural Environment and External Factors in Following Plant-Based Diets

A general transition to plant-based diets is recommended for improved human and planetary health. The information about why people opt for plant-based diets can be used to profile future health promotion initiatives. We studied the reasons that encouraged the adoption and maintenance of plant-based diets and the influence of the socio-cultural environment and other external factors. Through the use of a specifically designed questionnaire, we evaluated two different populations. Interpreting data from 229 participants, we observed the relevance of adapting strategies to motivate people to embrace plant-based diets according to their socio-cultural environment. External factors facilitating access to plant-based products appeared to be essential in both populations.

The Removal of Residual Concentration of Hazardous Metals in Wastewater from a Neutralization Station Using Biosorbent-A Case Study Company Gutra, Czech Republic

This article deals with the possibility of using a biosorbent in the form of a mixture of cones from coniferous trees to remove the residual concentration of hazardous metals contained in hazardous waste, which is disposed of in a neutralization station. The efficiency of the tested biosorbent in removing Ni, Zn, Cu, and Fe was monitored here. Laboratory research was carried out before the actual testing of the biosorbent directly in the operation of the neutralization station. With regard to the planned use of the biosorbent in the operational test, the laboratory experiments were performed in a batch mode and for the most problematic metals (Ni and Zn). The laboratory tests with real wastewater have shown that the biosorbent can be used to remove hazardous metals. Under the given conditions, 96% of Ni and 19% of Zn were removed after 20 min when using NaOH activated biosorbent with the concentration of 0.1 mol L⁻¹. The inactivated biosorbent removed 93% of Ni and 31% of Zn. The tested biosorbent was also successful during the operational tests. The inactivated biosorbent was applied due to the financial costs. It was used for the pre-treatment of hazardous waste in a preparation tank, where a significant reduction in the concentration of hazardous metals occurred, but the values of Ni, Cu, and Zn still failed to meet the emission limits. After 72 h, we measured 10 mg L⁻¹ from the original 4,056 mg L⁻¹ of Ni, 1 mg L⁻¹ from the original 2,252 mg L⁻¹ of Cu, 1 mg L⁻¹ from the original 4,020 mg L^–1 of Zn, and 7 mg L⁻¹ from the original 1,853 mg L⁻¹ of Fe. However, even after neutralization, the treated water did not meet the emission limits for discharging into the sewer system. The biosorbent was, therefore, used in the filtration unit as well, which was placed in front of the Parshall flume. After passing through the filtration unit, the concentrations of all the monitored parameters were reduced to a minimum, and the values met the prescribed emission limits. The biosorbent was further used to thicken the residual sludge in the waste pre-treatment tank, which contributed to a significant reduction in the overall cost of disposing of residual hazardous waste. This waste was converted from liquid to solid-state.

Dietas saudáveis e sustentáveis no âmbito do sistema alimentar no século XXI

RESUMO O objetivo deste ensaio foi o de realizar análise reflexiva sobre o tema das dietas sustentáveis, salientando a necessidade de debater o que seria uma alimentação adequada, dado o impacto ambiental do sistema alimentar atual. Inicia-se com uma digressão sobre a construção dessa temática para, na sequência, traçar paralelos entre dietas saudáveis e sustentáveis. Para tanto, utilizaram-se bases de dados e literatura cinzenta. O conceito de dietas sustentáveis vem sendo construído com o objetivo de agregar às preocupações nutricionais, culturais e econômicas, as questões ambientais que envolvem todo o sistema alimentar, pensando a garantia de Segurança Alimentar e Nutricional no presente e futuro. No entanto, as pesquisas realizadas têm mostrado a complexidade em conjugar todas essas preocupações na formulação de uma dieta adequada. Em linhas gerais, autores estudados concordam que uma alimentação com baixo impacto ambiental é geralmente consistente com uma boa nutrição. Porém, mesmo dentro desses padrões alimentares, haverá alguns alimentos mais sustentáveis do que outros, baseados em fatores da cadeia de suprimentos, dependendo de como e onde os alimentos foram produzidos, fabricados e transportados. O campo científico da nutrição e as diretrizes e políticas alimentares devem dar a devida consideração à sustentabilidade ao estabelecer metas voltadas para a nutrição saudável.

Effects of Food Constituents on Absorption and Bioaccessibility of Dietary Synthetic Phenolic Antioxidant by Caco-2 Cells

One typical synthetic phenolic antioxidant 2,6-di-tert-butyl-hydroxytoluene (BHT) is widely used in foodstuff. Concerns are rising on the toxicity of BHT and its metabolites through dietary exposure. In this study, the effects of food macronutrients (i.e., lipid, carbohydrate, fiber, protein, and fasted (as control)) on absorption and bioaccessibility of BHT by Caco-2 cells were investigated. Food components decreased the absorption and bioaccessibility by Caco-2 cells. The highest absorption rate by Caco-2 cells was fasted state (first-order rate constant = 4.26 h^-1), followed by carbohydrate (2.36 h^-1), fiber (1.39 h^-1), lipid (1.34 h^-1), and protein (1.15 h^-1). The order of bioaccessibility of BHT and its metabolites was fasted (100 ± 11.5%) > protein (83.1 ± 2.69%) > fiber (65.8 ± 2.67%) > carbohydrate (56.8 ± 1.58%) ≈ lipid (56.7 ± 0.82%). A solid-phase microextraction test together with a computational in vitro kinetic model suggested that the macronutrients may bind to BHT to reduce its free concentration and decrease the bioaccessibility. To our knowledge, this is the first study to report food influence on the absorption and bioaccessibility of BHT by Caco-2 cells. Results here can provide important implications for the safety regulation for dietary synthetic phenolic antioxidants.

Mediterranean Diet and its Environmental Footprints amid Nutrition Transition: The Case of Lebanon

Many Mediterranean countries, including Lebanon, are experiencing a shift in food consumption away from the traditional Mediterranean diet (MD), concomitant with the escalating burden of non-communicable diseases and dwindling environmental resources. Objective: to examine the adherence to the MD and its association with environmental footprints (EFPs), including water use, energy use, and greenhouse gas (GHG) emissions, among Lebanese adults. Data of Lebanese adults were drawn from the national food consumption survey (n = 2610). Assessment of dietary intake was conducted using a food-frequency questionnaire. Adherence to the MD was examined using four published MD scores. Metrics for the EFPs were calculated using a review of existing life cycle assessments (LCAs). For all MD scores, less than 13% of participants were in the highest tertile. After adjustments for covariates, two of the MD scores were associated with lower water use. For GHG, significant inverse associations were observed with all MD scores. Energy use was not associated with MD scores. Overall, low adherence to the MD among Lebanese adults was observed, together with an inverse association between adherence to the MD and water use and GHG emissions. These findings support and enforce ongoing efforts that aim to increase adherence to the MD in order to address health issues, as well as tackle environmental sustainability.

Vegetarian Diets: Planetary Health and Its Alignment with Human Health

To maintain planetary health, human activities must limit the use of Earth's resources within finite boundaries and avoid environmental degradation. At present, food systems account for a substantial use of natural resources and contribute considerably to climate change, degradation of land, water use, and other impacts, which in turn threaten human health through food insecurity. Additionally, current dietary patterns, rich in animal products and excessive in calories, are detrimental to both population and planetary health. In order to resolve the diet-environment-health trilemma, population-level dietary changes are essential. Vegetarian diets are reported to be healthy options. Most plant-sourced foods are less resource intense and taxing on the environment than the production of animal-derived foods, particularly meat and dairy from ruminants. This review article explores simultaneously the environmental sustainability of vegetarian diets, and its alignment with people's health. In general, the progression from omnivorous to ovolactovegetarian and vegan diets is associated with increased environmental sustainability. Greenhouse gas emissions resulting from vegan and ovolactovegetarian diets are ∼50% and ∼35% lower, respectively, than most current omnivore diets, and with corresponding reductions in the use of natural resources. Concomitant health benefits could be obtained by shifting from current dietary patterns to sustainable vegetarian diets. Thus, there seems to be an alignment of health and environmental outcomes for vegetarian diets. Although this shows the human health and environmental sustainability benefits of vegetarian diets in high-income countries, questions remain about the challenges in other contexts and the political will to promote meat-free diets as the social norm.

Alimentação saudável e sustentável: uma revisão narrativa sobre desafios e perspectivas

Resumo Parte-se do princípio que um sistema alimentar insustentável não é capaz de produzir alimentos saudáveis para o consumo. A alimentação só pode ser considerada saudável se for também sustentável, devendo ultrapassar a perspectiva nutricional. Assim, realizou-se uma revisão narrativa de literatura acerca de sistemas alimentares saudáveis e sustentáveis, englobando aspectos de produção, processamento, comercialização e consumo, visando levantar seus desafios e perspectivas de consolidação. A alimentação saudável e sustentável deve estar relacionada à produção de alimentos que protejam a biodiversidade e promovam o consumo variado, resgatando alimentos, preparações e hábitos culturais tradicionais. Deve ser acessível e disponível a todos, em quantidade e qualidade, baseada em alimentos produzidos e processados na região, por agricultores familiares, de maneira agroecológica, fundamentada na comercialização justa, aproximando a produção do consumo. Além disso, deve ser isento de contaminantes físicos, biológicos ou químicos que causem malefícios a todos os envolvidos, de maneira aguda ou crônica.

Reducing Ammonia Emissions from Dairy Cattle Production via Cost-Effective Manure Management Techniques in China

This study analyzed ammonia reduction potential and related costs and benefits of several ammonia emission reduction technologies applicable for dairy production from cattle in China. Specifically, these included diet manipulation, manure acidification, manure/slurry covers, and solid manure compaction. Ammonia emissions for China were estimated using the GAINS and NUFER models, while mitigation potentials of technologies were determined from laboratory studies. Ammonia reduction potentials from dairy production in China ranged from 0.8 to 222 Gg NH₃ year^-1 for the selected technologies. Implementation costs ranged from a savings of US$15 kg^-1 NH₃ abated to an expenditure of US$45 kg^-1 NH₃ abated, while the total implementation costs varied from a savings of US$1.5 billion in 2015 to an expenditure of a similar size. The best NH₃ reduction technology was manure acidification, while the most cost-effective option was diet optimization with lower crude protein input. For most abatement options, material costs were the critical element of overall costs. The fertilizer value of manure could partly offset the implementation cost of the options tested. Furthermore, benefits due to avoided health damage, as a result of reducing NH₃ emissions, could make all abatement options (except for manure compaction) profitable on the scale of a national economy.

Sustainability Matters: Consumer Acceptance of Different Vertical Farming Systems

Fresh produce within vertical farming systems grows vertically in different layers stacked atop each other, thus allowing for the efficient use of space. As the environment in vertical farming systems is completely controlled, neither sunlight nor soil is necessary. On the one hand, vertical farming may help to provide a healthy diet for the growing global population because it has a greater crop yield per square meter used than conventional farming; moreover, it can offer the opportunity to grow food in climatically disadvantaged areas. On the other hand, growth conditions may be perceived as unnatural and the entire vertical farming system as unsustainable. Therefore, understanding the consumers’ acceptance of vertical farming systems is important. This study is the first work to provide insights into consumers’ acceptance of three different vertical farming systems. Data are collected through an online survey of 482 consumers in Germany in February 2018. Drivers of consumer acceptance of vertical farming systems are identified through structural equation modelling. The results indicate that perceived sustainability is the major driver of consumer acceptance of vertical farming systems. The larger the system, the higher the likelihood that it will be considered as sustainable. Obviously, consumers perceive something like ecologies of scale.

Benefits of the Mediterranean diet: Epidemiological and molecular aspects

More than 50 years after the Seven Countries Study, a large number of epidemiological studies have explored the relationship between the Mediterranean diet (MD) and health, through observational, case-control, some longitudinal and a few experimental studies. The overall results show strong evidence suggesting a protective effect of the MD mainly on the risk of cardiovascular disease (CVD) and certain types of cancer. The beneficial effects have been attributed to the types of food consumed, total dietary pattern, components in the food, cooking techniques, eating behaviors and lifestyle behaviors, among others. The aim of this article is to review and summarize the knowledge derived from the literature focusing on the benefits of the MD on health, including those that have been extensively investigated (CVD, cancer) along with more recent issues such as mental health, immunity, quality of life, etc. The review begins with a brief description of the MD and its components. Then we present a review of studies evaluating metabolic biomarkers and genotypes in relation to the MD. Other sections are dedicated to observation and intervention studies for various pathologies. Finally, some insights into the relationship between the MD and sustainability are explored. In conclusion, the research undertaken on metabolomics approaches has identified potential markers for certain MD components and patterns, but more investigation is needed to obtain valid measures. Further evaluation of gene-MD interactions are also required to better understand the mechanisms by which the MD diet exerts its beneficial effects on health. Observation and intervention studies, particularly PREDIMED, have provided invaluable data on the benefits of the MD for a wide range of chronic diseases. However further research is needed to explore the effects of other lifestyle components associated with Mediterranean populations, its environmental impact, as well as the MD extrapolation to non-Mediterranean contexts.

Environmental impacts of dietary quality improvement in China

Dietary-related risks rank top among all the health risks in many countries. The 2nd United Nations Sustainable Development Goal aims to end hunger, achieve food security and improved nutrition and promote sustainable agriculture. Yet whether improving nutritional quality also benefits the environment is still under-explored, particularly for developing countries. China is an interesting and important case because of its rapidly changing dietary patterns distinct from the western countries studied in the literature, sub-national level heterogeneity, socio-economic characteristics and lifestyles, as well as its considerable population. This paper evaluates greenhouse gas (GHG) emissions, water consumption, and land appropriation resulting from shifting the Chinese population to healthy diets. We quantify the environmental impacts of individual diets using the latest available data of China Health and Nutrition Survey (2011), and compare them with the environmental impacts of suggested healthy dietary patterns in accordance with the 2016 Chinese Dietary Guidelines. If all Chinese would follow healthy diets rather than their current diets revealed in the survey, GHG emissions, water consumption, and land occupation would increase by 7.5% (63.9 Mt CO₂e annually), 53.5% (510 billion m³), and 54.2% (1256 billion m²), respectively. Urban and high-income groups have higher diet-related environmental impacts but could achieve less additional environmental impacts when moving to healthier diets. These findings indicate an expense of increased GHG emissions, and consumption of water and land resources in improving health. They also highlight the need to focus on the effects of improved economic conditions and urbanization in reconciling environmental impacts and human nutritional adequacy.

Integrating Protein Quality and Quantity with Environmental Impacts in Life Cycle Assessment

Life cycle assessment (LCA) evaluates environmental impacts of a product from material extraction through disposal. Applications of LCA in evaluating diets and foods indicate that plant-based foods have lower environmental impacts than animal-based foods, whether on the basis of total weight or weight of the protein content. However, LCA comparisons do not differentiate the true biological value of protein bioavailability. This paper presents a methodology to incorporate protein quality and quantity using the digestible indispensable amino acid score (DIAAS) when making comparisons using LCA data. The methodology also incorporates the Food and Drug Administration’s (FDA) reference amounts customarily consumed (RACCs) to best represent actual consumption patterns. Integration of these measures into LCA provides a mechanism to identify foods that offer balance between the true value of their protein and environmental impacts. To demonstrate, this approach is applied to LCA data regarding common protein foods’ global warming potential (GWP). The end result is a ratio-based score representing the biological value of protein on a GWP basis. Principal findings show that protein powders provide the best efficiency while cheeses, grains, and beef are the least efficient. This study demonstrates a new way to evaluate foods in terms of nutrition and sustainability.

Use of Bio-Based Plastics in the Fruit Supply Chain: An Integrated Approach to Assess Environmental, Economic, and Social Sustainability

The challenge of developing a sustainable production system includes the reduction of emissions, the efficient use of resources, and the transition to renewable energy. The bioeconomy proposes a development model aimed at reducing impacts and risks associated with the use of non-renewable resources considering the life cycle of products. The European Union is promoting products from renewable sources focused on biochemicals and bio-based plastics, which are high added value products when compared to biofuels. The aim of this paper is to consider sustainability in terms of the environmental, economic, and social aspects of use of bio-based plastics in the fruit chain, considering the case study of raspberry supply chains in northwestern Italy. Different analyses (life-cycle assessment (LCA), life-cycle costing (LCC), and externality assessment (ExA)) were used to assess the impacts along the whole chain by means of an integrated approach. The results show that the bio-based plastic scenario has lower environmental and social impacts than the conventional one, whereas the latter is the best choice according to a classic economic approach. The introduction of bio-based plastics as a replacement for traditional plastics in agri-food chains is the first step toward the use of renewable resources with a low impact on society.

Global sustainability (health, environment and monetary costs) of three dietary patterns: results from a Spanish cohort (the SUN project)

OBJECTIVE

To evaluate the sustainability of the dietary patterns, according to their effects on health and environment and their affordability.

DESIGN

Prospective, ongoing cohort study of university graduates.

SETTINGS

The Spanish SUN project (Seguimiento Universidad de Navarra, University of Navarra Follow-up), starting from 1999.

PARTICIPANTS

A total of 18 429 participants.

METHODS

Information from participants is collected every 2 years by validated questionnaires. We assessed three dietary patterns (the Mediterranean, the Western and the Provegetarian dietary patterns). The rate advancement period (RAP) was used to assess the healthiness of each pattern (considering the composite endpoint of all-cause mortality, cardiovascular disease, breast cancer or type 2 diabetes). We also assessed environmental footprints and monetary costs of each dietary pattern.

RESULTS

After a median follow-up of 10.1 years, we identified 469 incident cases of the composite endpoint. The Mediterranean dietary pattern exhibited the best RAP (3.10 years gained [95% CI 4.35 to 1.85] for the highest vs the lowest quartile), while the Western pattern was the unhealthiest pattern (1.33 years lost when comparing extreme quartiles). In a scale between 4 and 16 of harmful environmental effects (the lower, the more environmentally friendly), the Provegetarian pattern scored best (8.82 [95% CI 8.75 to 8.88] when comparing extreme quartiles), whereas the Western pattern was the most detrimental pattern (10.80 [95% CI 10.72 to 10.87]). Regarding monetary costs, the Western pattern was the most affordable pattern (€5.87/day [95% CI 5.82 to 5.93], for the upper quartile), while the Mediterranean pattern was the most expensive pattern (€7.52/day [95% CI 7.47 to 7.56]). The Mediterranean dietary pattern was the most overall sustainable option, closely followed by the Provegetarian pattern. The least overall sustainable pattern was the Western dietary pattern.

CONCLUSION

Following plant-based diets, like the Mediterranean or Provegetarian dietary patterns, could be a good option in order to achieve an overall sustainable diet.

TRIAL REGISTRATION NUMBER

NCT02669602; Results.

Towards an environmentally sustainable and healthy Atlantic dietary pattern: Life cycle carbon footprint and nutritional quality

Production and consumption of food has a significant effect on climate change. The effect of different consumption habits on the environment should not be under estimated, as there are different studies that mention the environmental impact associated with different foods, especially those of animal origin. The analysis of the Atlantic diet (AD), as the most common dietary pattern in Northwestern Spain, serves as an example of a diet with a high consumption of local, fresh and seasonal products, home cooking and low-processed foods. The evaluation was carried out by quantifying the carbon footprint following the Life Cycle Analysis methodology and identifying its nutritional quality according to the value of the Nutrient-rich Dietary index (NRD9.3.). According to the main results, the consumption of livestock products and shellfish is responsible for most GHG emissions (70% of the total). The basic ingredients of the AD, such as vegetables and legumes, make a relatively minor contribution (with an impact of 30% of the total) to the total carbon footprint of 3.01 kg CO₂eq·person^-1·day^-1. As regards nutritional quality, AD has a high nutritional score (474), mainly due to the low intake of sodium, added sugars and saturated fats (nutrients to be limited in healthy diets). In general, both the carbon footprint and the nutritional index score are consistent with those of other studies on the Mediterranean diet, which has been recognised as beneficial. Therefore, it can be concluded that the AD may be recommended from a nutritional and environmental point of view, mainly due to the high intake of fish and vegetables. The communication of this valuable environmental and nutritional information to consumers should be taken into account when considering strategic actions for the adoption of healthy and sustainable dietary patterns.

Characterizing diversity of food systems in view of sustainability transitions. A review

Dominant food systems are configured from the productivist paradigm, which focuses on producing large amounts of inexpensive and standardized foods. Although these food systems continue being supported worldwide, they are no longer considered fit-for-purpose as they have been proven unsustainable in environmental and social terms. A large body of scientific literature argues that a transition from the dominant food systems to alternative ones built around the wider principles of sustainable production and rural development is needed. Promoting such a sustainability transition would benefit from a diagnosis of food system types to identify those systems that may harbor promising characteristics for a transition to sustainable food systems. While research on food system transitions abounds, an operational approach to characterize the diversity of food systems taking a system perspective is still lacking. In this paper we review the literature on how transitions to sustainable food systems may play out and present a framework based on the Multi-Level Perspective on Socio-Technical Transitions, which builds upon conceptual developments from social and natural science disciplines. The objectives of the framework are to (i) characterize the diversity of existing food systems at a certain geographical scale based on a set of structural characteristics and (ii) classify the food systems in terms of their support by mainstream practices, i.e., dominant food systems connected to regimes; deviate radically from them, niche food systems such as those based on grassroots innovation; or share elements of dominant and niche food systems, i.e., hybrid food systems. An example is given of application of our framework to vegetable food systems with a focus on production, distribution, and consumption of low-or-no pesticide vegetables in Chile. Drawing on this illustrative example we reflect on usefulness, shortcomings, and further development and use of the diagnostic framework.

Carbon footprint and nutritional quality of different human dietary choices

Apart from industrial activities, our eating habits also have a significant environmental cost associated with crop cultivation, manufacturing processes, packaging, refrigeration, transport cooking and waste management. In a context of growing social awareness of the role of different dietary choices in the environment, the review of different alternatives on the road to a healthy and sustainable diet should integrate relevant information on the nutritional quality of different eating habits. Since dietary choices have an effect on environmental sustainability and human health, a literature review on different dietary choices has been conducted to determine the differences in carbon footprint and nutritional quality identifying the main hotspots trying to give advice towards the identification of sustainable diets. After applying a set of criteria for reference selection, 21 peer-reviewed studies have been analysed in detail, allowing the comparison of 66 dietary scenarios. We identified that the so-called Mediterranean and Atlantic diets present high nutritional scores and low carbon footprints. On the contrary, the dietary choices identified in northern and Western Europe, as well as in the United States, have the highest carbon footprints, highlighting the contribution of dairy products as a basic source of high-quality nutrients and protein. Broadly speaking, dietary choices rich in vegetables (e.g., vegan, vegetarian as well as Indian and Peruvian) have a better environmental profile than those rich in meat (mainly ruminant meat). In line with these findings, the shift in meat consumption habits from beef and veal to chicken, pork and poultry, the introduction of alternative foods to animal protein (e.g. quinoa) and the consumption of olive oil as a major source of vegetable oil may be compatible with a healthier and more environmentally friendly diet. However, the complete elimination of meat and dairy products from the daily diet may not be feasible in case the supply of some micronutrients (e.g., calcium and vitamin D) is not guaranteed. Limitations were identified in the consulted studies related to the consideration of the different system boundaries, as well as underlying uncertainties related to data sources. Therefore, efforts should be made to develop consistent and agreed-upon methods for estimating both the carbon footprint and nutritional quality scores.