Multi-Objective Optimization of Nutritional, Environmental and Economic Aspects of Diets Applied to the Spanish Context

Environmental sustainability and nutritional quality of different diets considering nutritional adequacy

This study examines how four diets change nutritionally and environmentally when the diets are nutritionally adjusted. Data on individual Belgian diets of omnivores (n = 131), pescovegetarians (n = 159), vegetarians (n = 494), and vegans (n = 78) were obtained, called non-adjusted diets. We assessed if diets met energy and nutrient intake requirements and calculated the Alternative Healthy Eating Index (AHEI)-2010. The environmental impact was evaluated by a cradle-to-grave life cycle assessment considering all midpoint indicators of the Environmental Footprint 3.0 and expressing the impact per "daily food and supplement intake by one Belgian adult". The individual dietary intakes were adjusted nutritionally to meet the recommended energy and nutrition intakes using a quadratic programming algorithm. All diets had a significantly improved AHEI score but also a significantly increased water use (WU) when adjusting. The omnivore's diet demonstrated a significantly decreased carbon footprint (CF) while it significantly (except for vegans) raised for the restrictive diets due to adjustment. The omnivorous diet had the greatest improvements in AHEI (15.4), while WU increased the most among all diets (3.7 m3), primarily due to elevated fruit intake. The CF was reduced with 1.2 kg CO2 due to decreased red meat consumption. The AHEI of the vegan diet improved the second most of all diets (13.2) due to the intake of omega-3 supplements, while its WU rose the least of all diets (2.4 m3), and its CF barely increased (0.1 kg CO2-eq). The AHEI improvements of the vegetarian diet were similar to those of the vegan diet (12.5), while the one of the pescovegetarian diet was limited (3.5). The (pesco)vegetarian diet had an increase in WU (2.5 and 2.7 m3) and the highest increase in the CF (0.3 kg CO2-eq). Since nutritionally adjusted diets do not lead to similar nutritional and environmental improvements, this research highlights the need to assess both metrics.

Can micronutrient requirements be met by diets from sustainable sources: outcomes of dietary modelling studies using diet optimization

BACKGROUND

Consumption of diets from sustainable sources is required for planetary health, however, large sections of the population, including females of reproductive age and children, will be at risk of not meeting their micronutrient (MN) requirements in a complete transition to plant-based foods. Constrained diet optimization methods use mathematical programming to construct diets that meet predefined parameters and may contribute towards modelling dietary solutions that meet nutritional and planetary targets.

OBJECTIVE

Review the evidence from diet optimization studies proposing solutions to ensure MN availability in the context of a transition to diets from sustainable sources.

APPROACH

Narrative review focusing on literature published over the last five years.

RESULTS

Dietary modelling using diet optimization can design a range of omnivorous and plant-based diets that meet individual MN requirements, have reduced environmental impacts, and minimize deviation from culturally acceptable dietary practices. Using data from large-scale dietary surveys, diet optimization can support development of food-based dietary guidelines; identify limiting MNs in a particular context or a conflict between constraints e.g. nutrition and environment; explore food-based strategies to increase nutrient supply, such as fortification; and support trial design. Methods used and outcomes reported are sources of variability. Individual-level dietary data and MN requirements for population sub-groups such as females of reproductive age and children are important requirements. Although maintaining iron and zinc intakes are regularly reported to present challenges in diets from sustainable sources, few studies have considered bioavailability, which reduces with increased dietary phytate. These and other data gaps including acceptability and affordability must be addressed to improve the applicability of modelling outcomes in population recommendations.

CONCLUSIONS

Dietary modelling using diet optimization can be useful in the design of more sustainable diets that meet MN requirements, however, translation of outcomes into dietary intervention studies is required to test real-world application and adoption into dietary guidelines.

Prospective life cycle assessment of climate and biodiversity impacts of meat-based and plant-forward meals: A case study of Indonesian and German meal options

The emerging field of prospective life cycle assessment (pLCA) offers opportunities for evaluating the environmental impacts of possible future consumption shifts. One such shift involves a transition from meat-based to plant-forward diets, acknowledged to mitigate environmental impacts of the food system under present day conditions. Current diets are often meat intensive ("meat-based"), whilst "plant-forward" diets include mainly plant-based foods, encompassing flexitarian, vegetarian, and vegan diets. Here we illustrate the application of pLCA in a case study of meal options, implementing shared socio-economic pathway scenarios in the LCA background system to represent future production conditions. We assess the climate footprints and land-based biodiversity footprints of a typical meat-based meal in Germany and Indonesia compared to a plant-forward meal in both countries (i.e., four meals), now and in 2050. Our findings show that the plant-forward alternative maintains a lower impact per serving in all future scenarios. At the same time, the reduction in impact for the meat-based meals is more pronounced in future scenarios due to shifts in the agricultural system. Our findings highlight the importance of supply-side measures to produce lower-impact ingredients, complementing demand-side interventions to reshape food consumption. Results are further evaluated in cultural and nutritional contexts, highlighting the practical decision-making constraints faced by consumers. We find potential "leakage" effects in calories and nutrition when choosing a lower-impact, plant-forward meal. These leakage effects should be considered in future studies seeking to evaluate the environmental implications of meal substitutions in the context of broader dietary requirements.

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.

European dietitians as key agents of the green transition: An exploratory study of their knowledge, attitudes, practices, and training

Introduction

How food systems are currently provisioning food to the population is a matter of debate worldwide. Food systems, driven by widespread and increasing adherence to a westernized dietary pattern, are failing to meet people's basic needs and are draining natural resources. There is a push to make food systems more healthy, fair, and sustainable. To this end, action from all players is needed to meet the international agenda. In this regard, dietitians play a crucial role, as they can provide advice and promote actions that foster the adoption of more sustainable dietary patterns (SDP) as well as the promotion of sustainable food systems. As an emerging requirement in their training, it is crucial to know what dietitians know about SDP as well as their attitudes and current practices in this field in order to strengthen their competences and be key agents for the green transition. For this reason, the aim of the present study is to explore the knowledge, attitudes, practices, and training (KAPT) of European dietitians on SDP by administering an online survey.

Methods

Cross-sectional survey administered between April-August 2021 to dietitians based in the European countries with National Dietetic Associations or Education Associate Members affiliated to the European Federation of Associations of Dietitians (EFAD). Results were analyzed based on European region of professional practice (Northern/Southern/Western/South-East Europe), area of expertise and years of experience.

Results

Responses from 2211 dietitians from 25 countries were received, although the analysis was based on those that responded at least 90% of the survey (n=208). European dietitians are lacking training on SDP but are willing to learn more about it. Most dietitians perceive themselves as able to define an SDP, although aspects concerning social and economic sustainability were underestimated. Dietitians concur that barriers exist to the promotion of SDP, such as the lack of updated national food-based dietary guidelines and the absence of support from peers and managers. The country of professional activity seemed to be key to influencing dietitians' KAPT.

Discussion

These results emphasize the need to strengthen European dietitians' training in SDP and increase public/private commitment to consider dietitians as key professionals for the transition towards SDP.

Dietary Change and Global Sustainable Development Goals

Food production for human consumption is a leading cause of environmental damage in the world and yet over two billion people suffer from malnutrition. Several studies have presented evidence that changes in dietary patterns across the world can lead to win-win outcomes for environmental and social sustainability and can complement ongoing technological and policy efforts to improve the efficiency of agricultural production. However, the existing evidence have been compiled in “silos” by a large range of researchers across several disciplines using different indicators. The aim of this quantitative review is to bring together the existing knowledge on heterogeneity of current dietary patterns across the world and how a transition toward healthy diets in different countries can aid in progress toward multiple global Sustainable Development Goals (SDGs). We first summarize the nutritional quality, economic cost, and environmental footprint of current diets of over 150 countries using multiple indicators. Next, we review which shifts in dietary patterns across different world regions can help toward achievement of SDG2 (Zero hunger), SDG3 (Good health and wellbeing), SDG 6 (Clean water and sanitation), SDG13 (Climate action), SDG14 (Life below water), and SDG15 (Life on land). Finally, we briefly discuss how to enable the shift toward sustainable dietary patterns and identify the research and data gaps that need to be filled through future efforts. Our analysis reveals that dietary change is necessary in all countries as each one has unique priorities and action items. For regions such as Sub-Saharan Africa and South Asia, increased intake of nutrient dense foods is needed to address deficiency of essential nutrients like folate, potassium, and vitamin A. For North America and Europe, shifting toward more plant-based diets would be healthier and simultaneously reduce the per capita environmental footprints. The results can be useful for policymakers in designing country-specific strategies for adoption of sustainable dietary behaviors and for food industry to ensure the supply of sustainable food items customized with regions' need.

Environmental Impact of Meals: How Big Is the Carbon Footprint in the School Canteens?

The inhabitants of the world are expected to grow by two billion in the next two decades; as population increases, food demand rises too, leading to more intensive resource exploitation and greater negative externalities related to food production. In this paper the environmental impact of meals provided in school canteens are analysed through the Life Cycle Assessment methodology, in order to evaluate the GHGs emissions released by food production. Meals, and not just individual foods, have been considered so as to include in the analysis the nutritional aspects on which meals are based. Results shows that meat, fish and dairy products are the most impacting in terms of greenhouse gas emissions, with values that shift from 31.7 and 24.1 kg CO₂ eq for butter and veal, to 2.37 kg CO₂ eq for the octopus, while vegetables, legumes, fruit and cereals are less carbon intensive (average of 3.71 kg CO₂ eq for the considered vegetables). When the environmental impact is related to the food energy, the best option are first courses because they combine a low carbon footprint with a high energy content. The results of the work can be used both by the consumer, who can base the meal choice on environmental impact information, and by food services, who can adjust menus to achieve a more sustainable production.

Role of the Food Supply Chain Stakeholders in Achieving UN SDGs

This paper gives an overview of main food supply chain stakeholders and their role in achieving the UN Sustainable Development Goals (SDGs). As this supply chain is global, playing a significant role in feeding the world, a deeper analysis of 17 SDGs, their targets and indicators reveals numerous direct and indirect connections with various SDGs. To perform such an overview, the authors investigated the link between the main stakeholders of the chain (farmers, food processors, food traders and consumers) with UN SDGs. In parallel, the authors explored the roles of policymakers, inspection services, certification bodies and academia in supporting these SDGs. In spite of numerous papers, calculations and estimations, discussion and media coverage, the authors believe that only the tip of the iceberg has been revealed. Based on this overview, the authors emphasize SDG 2—Zero Hunger and SDG 12—Responsible Consumption and Production as the most dominant for the food supply chain. In parallel, the achievement of SDG 17—Partnerships for the Goals will enable deeper intertwining of the goals and all stakeholders in the food supply chain continuum. Additional efforts are needed to pave the way for fulfilling the targets of the UN SDGs and exceeding expectations of all stakeholders.