The Future of Plant-Based Diets: Aligning Healthy Marketplace Choices with Equitable, Resilient, and Sustainable Food Systems

The future of plant-based diets is a complex public health issue inextricably linked to planetary health. Shifting the world's population to consume nutrient-rich, plant-based diets is among the most impactful strategies to transition to sustainable food systems to feed 10 billion people by 2050. This review summarizes how international expert bodies define sustainable diets and food systems and describes types of sustainable dietary patterns. It also explores how the type and proportion of plant- versus animal-source foods and alternative proteins relate to sustainable diets to reduce diet-related morbidity and mortality. Thereafter, we synthesize evidence for current challenges and actions needed to achieve plant-based sustainable dietary patterns using a conceptual framework with principles to promote human health, ecological health, social equity, and economic prosperity. We recommend strategies for governments, businesses, and civil society to encourage marketplace choices that lead to plant-rich sustainable diets within healthy, equitable, and resilient agroecological food systems.

Environmental assessment of diets: overview and guidance on indicator choice

Comprehensive but interpretable assessment of the environmental performance of diets involves choosing a set of appropriate indicators. Current knowledge and data gaps on the origin of dietary foodstuffs restrict use of indicators relying on site-specific information. This Personal View summarises commonly used indicators for assessing the environmental performance of diets, briefly outlines their benefits and drawbacks, and provides recommendations on indicator choices for actors across multiple fields involved in activities that include the environmental assessment of diets. We then provide recommendations on indicator choices for actors across multiple fields involved in activities that use environmental assessments, such as health and nutrition experts, policy makers, decision makers, and private-sector and public-sector sustainability officers. We recommend that environmental assessment of diets should include indicators for at least the five following areas: climate change, biosphere integrity, blue water consumption, novel entities, and impacts on natural resources (especially wild fish stocks), to capture important environmental trade-offs. If more indicators can be handled in the assessment, indicators to capture impacts related to land use quantity and quality and green water consumption should be used. For ambitious assessments, indicators related to biogeochemical flows, stratospheric ozone depletion, and energy use can be added.

Indices for measurement of sustainable diets: A scoping review

INTRODUCTION

The current food system is associated with negative impacts on health, food insecurity and environmental harm. Sustainable diets have attracted increasing interest and novel proposals with a global scope have emerged. This scoping review aims to give an overview of the analysis of all the available evidence related to the sustainable diet indices that have been developed based on the EAT-Lancet Commission.

METHODS

Searches were conducted in the PubMed, Embase, Web of Science, Scopus and Science Direct databases. This review was conducted following the PRISMA-ScR guidelines. The target population were studies addressed the use of an index or metric for assessing sustainable diets based on the EAT-Lancet Commission Summary Report were included. PCC acronym was used in the design of the study to describe eligibility criteria: P (Population)-Indexes; C (Concept)-Sustainable diets; C (Context)-Knowledge on the structure and applicability of measurement indices of sustainable diets based on EAT-Lancet recommendations available in the literature. Study eligibility criteria were restricted to papers published in English, from January 2019 through October 2022, with no population restriction.

RESULTS

A total of 1,458 papers were retrieved, 14 of which were included in the review. Seven measures of sustainable diets were identified as follow: EAT-Lancet diet score (ELD-I), New EAT-Lancet diet score (EAT), Planetary Health Diet Index (PHDI), Sustainable Diet Index (SDI), Sustainable-HEalthy-Diet (SHED), novel Nutrient-Based EAT index (NB-EAT) and World Index for Sustainability and Health (WISH). Most studies were conducted in developed countries, where greater adherence to this type of diet was found. Estimated greenhouse gas emissions was the most reported indicator of sustainability, followed by diet quality and the benefits of sustainable diets with regards to health outcomes.

DISCUSSION

We identified barriers that hinder progress towards sustainable diets, including the difficulty of comparing different indices and the tendency to neglect social aspects and the lack of common definitions and metrics. Despite being challenge, we highlight the importance of using indices that assess sustainable diets that harmonize various indicators, as recommended by the EAT-Lancet Commission, in order to promote positive changes towards a more sustainable future.

Dynamic implications of the biological link between bovine milk and meat production for operationalizing the planetary health diet

The EAT-Lancet planetary health diet (PHD) provides guidelines on a global scale and calls for red meat consumption to be halved. Operational PHD guidelines at country level have yet to be determined. Here we argue that the biological link between milk and bovine-meat production must be considered when operationalizing the globally calculated PHD to national contexts. Using a stylized computer simulation model rooted in a food system approach, we explore the impact of dietary scenarios on milk and bovine-meat production and show that ignoring this biological link can lead to substantial imbalances between national dietary guidelines and production outcomes and potentially lead to food waste. Furthermore, we assess current national dietary guidelines in Europe and find that most disregard this biological link and are incompatible with the PHD, with implications for policymakers and consumers to consider when adapting the PHD in national contexts.

Consumer attitudes and behaviors toward more sustainable diets: a scoping review

There is an urgent need to move toward more sustainable diets. Although this will require radical and systemic changes across food systems, altering consumer ideologies and practices is essential to garner support for such actions. In this scoping review, the evidence on consumers' attitudes and behaviors toward more sustainable diets is synthesized and a range of factors, considerations, and proposed strategies are presented that can contribute to building the societal-level support for urgent and systems-level changes. The findings suggest that consumers, insofar as they are interested in sustainability and have the capacity to engage with the concept, primarily approach the concept of sustainable diet from a human health perspective. However, the interconnectedness of human health and well-being with environmental health is poorly understood and under-researched in the context of consumer behaviors and attitudes toward sustainable diets. This highlights the need for (1) sustained efforts from public health professionals to encourage a realignment of the term sustainable diet with its multidimensional meaning by championing an ecological public health approach in all efforts aimed at promoting more sustainable consumption, from awareness raising to policy development; (2) a broader research lens focused on the multidimensional concept of sustainability in the literature exploring consumer attitudes and behaviors; and (3) the development of multidisciplinary, clear, and evidence-based sustainable-eating messages, including holistic sustainable dietary guidance, to address knowledge gaps, minimize conflicting narratives, and build consumer agency. The findings contribute to understanding how support can be generated for the necessary structural and system-level changes required to support behavior change.

Focus of Sustainable Healthy Diets Interventions in Primary School-Aged Children: A Systematic Review

Research and public policy interest regarding Sustainable Healthy Diets (SHDs) have increased during the last decades, as nutrition recommendations and diet practices should align with growing environmental concerns. SHDs encompass sociocultural, economic and environmental components of nutrition and health and raising awareness across all these dimensions, as well as providing relevant education, especially to young children, is important for adopting SHD practices. Primary school students (5-12 years old) are often the target population for interventions, as they are considered agents of change for educating the community. The objective of this systematic review is to map the SHD indicators addressed by such interventions in order to identify gaps and opportunities for future interventions in this population. Scopus, PubMed and Web of Science were searched for available publications, following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA 2020) methodology. After screening for eligibility, thirteen intervention studies were included and reviewed. Results showed that indicator definitions and measuring methods were not harmonized across research efforts. Implemented SHD interventions address predominantly food waste and diet quality, while social and economic indicators are underrepresented. The standardization of SHD, focusing on measurable harmonized indicators, should be a priority for policy actors in order to enable impactful research efforts. Future interventions should incorporate clear SHD indicators to raise awareness and consider the application of composite tools or indexes to evaluate outcomes and maximize impact in the community.

Double- and triple-duty actions in childhood for addressing the global syndemic of obesity, undernutrition, and climate change: A scoping review

Obesity, undernutrition, and climate change constitute a global syndemic that disproportionately affects vulnerable populations, including children. Double- and triple-duty actions that simultaneously address these pandemics are needed to prevent further health, economic, and environmental consequences. Evidence describing the implementation and evaluation of such actions is lacking. This review summarized the literature on whole-of-population actions targeting children that were designed or adapted to be double or triple duty. Six academic databases were searched (January 2015-March 2021) using terms related to 'children', 'intervention', 'nutrition', 'physical activity', and 'climate change'. Data were extracted from 43/15,475 studies, including six randomized controlled trials. Most (58%) described triple-duty actions targeting food systems in schools such as implementing guidelines for healthier and environmentally sustainable school meals programs, and 51% reported engaging community in the design, implementation, and/or evaluation of actions. Changes in dietary intake, diet composition, greenhouse gas emissions, and food waste were the most frequently reported outcomes and 21 studies (three randomized controlled trials) showed positive double- or triple-duty effects. This review is the first to demonstrate that double- and triple-duty actions for addressing the global syndemic in childhood have been implemented and can have a positive impact on obesity, undernutrition, and climate change.

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.

Measuring sustainable consumer food purchasing and behavior

Consumer food purchasing and willingness to adopt a sustainable healthy diet (SHD) is a key factor affecting the sustainability of the entire food system. Studies have developed scales to measure consumer preferences for particular consumption patterns, while others have sought to empirically define the multiple dimensions of a sustainable food system (environmental, social, economic, etc.). This paper builds on these literatures by tracking consumers' SHD behaviors using a large-scale, longitudinal survey of adults in the United States and mapping them onto multiple systems-level indicators. We wanted to know whether consumers interact with the sustainability of their food along the same principles developed by experts. Our study defines 18 food purchasing behaviors that support the sustainability goals of leading scientific institutions, uses factor analysis to identify the unobserved drivers behind these behaviors, and creates SHD scores to investigate their correlations with other consumer characteristics and behaviors. Factor analysis results show consumer food purchasing is motivated by three underlying sustainability dimensions-Economic Security, Socio-Environment, and Nutrition-which are fewer constructs than often defined by academic researchers. SHD scores reveal higher adoption of behaviors that fall under Economic Security relative to the other two dimensions. All three sustainability constructs are impacted by socio-economic and demographic characteristics.

Basics of Sustainable Diets and Tools for Assessing Dietary Sustainability: A Primer for Researchers and Policy Actors

Climate change can have economic consequences, affecting the nutritional intake of populations and increasing food insecurity, as it negatively affects diet quality parameters. One way to mitigate these consequences is to change the way we produce and consume our food. A healthy and sustainable diet aims to promote and achieve the physical, mental, and social well-being of the populations at all life stages, while protecting and safeguarding the resources of the planet and preserving biodiversity. Over the past few years, several indexes have been developed to evaluate dietary sustainability, most of them based on the EAT-Lancet reference diet. The present review explains the problems that arise in human nutrition as a result of climate change and presents currently available diet sustainability indexes and their applications and limitations, in an effort to aid researchers and policy actors in identifying aspects that need improvement in the development of relevant indexes. Overall, great heterogeneity exists among the indicators included in the available indexes and their methodology. Furthermore, many indexes do not adequately account for the diets’ environmental impact, whereas others fall short in the economic impact domain, or the ethical aspects of sustainability. The present review reveals that the design of one environmentally friendly diet that is appropriate for all cultures, populations, patients, and geographic locations is a difficult task. For this, the development of sustainable and healthy diet recommendations that are region-specific and culturally specific, and simultaneously encompass all aspects of sustainability, is required.