Systematic Review of Dietary Patterns and Sustainability in the United States

Opportunities for Consistent and Holistic Metrics to Support Food Systems Transformation: A Summary of a Symposium Presented at Nutrition 2023

There is an urgent need for global food systems transformation to realize a future where planetary health reaches its full potential. Paramount to this vision is the ability of stakeholders across sectors to understand how foods and dietary patterns impact food systems inclusive of all domains of sustainability-environmental, nutrition/health, economic and social. This article is a synopsis of presentations by 3 food systems experts to share the latest science in a session entitled "How do you measure sustainability? Opportunities for consistent and holistic metrics to support food systems transformation" at the American Society for Nutrition's 2023 annual conference. As summarized here, global population data showing widespread malnutrition underscore the important role of dietary diversity through a balance of plant- and animal-source foods to achieve nutritionally adequate diets and reduce risk of noncommunicable diseases. Yet, recent international audits of countries, companies, and organizations and their sustainability targets largely demonstrate an underrepresentation of robust nutrition/health metrics to support public nutrition and health progress. Addressing limitations in diet-sustainability modeling systems provides a viable opportunity to accurately reflect the important contributions and trade-offs of diets across all domains of sustainability to ultimately support evidence-based decision making in advancing healthy food systems.

Changing sustainable diet behaviours during the COVID-19 Pandemic: inequitable outcomes across a sociodemographically diverse sample of adults

The objective of this study was to describe changes in sustainable dietary behaviours (those that support environmental, economic, and physical health) among a sample of US adults during the COVID-19 pandemic and to examine differences in changes by individuals' race/ethnicity and socioeconomic status. Therefore, a cross-sectional online survey study was conducted in April 2021 (N = 1,488, mean age = 42.7 (SD = 12.6)) receiving outpatient care from Michigan Medicine, the University of Michigan health system. Enrolment quotas were established to ensure a diverse sample-one-third of participants identified as African American/Black, one-third Hispanic/Latino, one-third White, and one-third low-income. Participants reported engaging in more behaviours that are supportive of a sustainable diet one year into the COVID-19 pandemic compared to before. This is particularly true regarding ecologically and economically sustaining behaviours such as taking fewer trips to the grocery store, increased use of home grocery delivery, increased cooking at home, and greater consumption of healthy foods. Not all behaviour changes promoted sustainable food systems; namely, the use of farmer's markets and Community Supported Agriculture (CSAs) declined. White and high-income participants were more likely than African American/Black, Hispanic/Latino, and low-income individuals to engage in ecologically and economically sustainable dietary behaviours during the pandemic. Meanwhile, African American/Black participants reported large increases in physical health sustainable dietary behaviours. To support the continuation of greater engagement with sustainable diets, policies that increase access to public transportation, limit the frequency with which consumers have groceries delivered, increase work-from-home options, and improve access for low-income populations should be prioritised.

Adherence to the Planetary Health Diet Index and correlation with nutrients of public health concern: an analysis of NHANES 2003-2018

BACKGROUND

The Planetary Health Diet Index (PHDI) is a novel measure adapted to quantify alignment with the dietary evidence presented by the EAT-Lancet Commission on Food, Planet, Health.

OBJECTIVES

To examine how population-level health and sustainability of diet as measured by the PHDI changed from 2003 to 2018, and to assess how PHDI correlated with inadequacy for nutrients of public health concern (iron, calcium, potassium, and fiber) in the United States.

METHODS

We estimated survey-weighted trends in PHDI scores and median intake of PHDI components in a nationally representative sample of 33,859 adults aged 20+ y from 8 cycles (2003-2018) of the National Health and Nutrition Examination Survey with 2 d of dietary recall data. We used the National Cancer Institute method to examine how PHDI correlated with inadequate intake of iron, calcium, potassium, and fiber.

RESULTS

Out of a theoretical range of 0-140, the median PHDI value increased by 4.2 points over the study period, from 62.7 (95% confidence interval [CI]: 62.0, 63.4) points in 2003-2004 to 66.9 (66.2, 67.7) points in 2017-2018 (P-trend < 0.001), although most of this change occurred before 2011-2012 and plateaued thereafter. For adequacy components that are encouraged for consumption, nonstarchy vegetable intake significantly decreased over time, whereas whole grains, nuts and seeds, and unsaturated oils increased. For moderation components with recommended limits for consumption, poultry and egg intake increased, but red and processed meat, added sugars, saturated fats, and starchy vegetables decreased over time. Higher PHDI values were associated with a lower probability of iron, fiber, and potassium inadequacy.

CONCLUSIONS

Although there have been positive changes over the past 20 y, there is substantial room for improving the health and sustainability of the United States diet. Shifting diets toward EAT-Lancet recommendations would improve nutrient adequacy for iron, fiber, and potassium. Policy action is needed to support healthier, more sustainable diets in the United States and globally.

Climate crisis and nephrology: a review of climate change's impact on nephrology and how to combat it

Climate change is worsening with tangible effects on our healthcare system. This review aims to examine the repercussions of the climate change on nephrology and explore potential strategies to mitigate its impact. This review examines dialysis's environmental impact, resource recycling methods, and plant-based diets for kidney health. Recent research highlights the advantages of plant-based diets in managing and preventing chronic kidney disease (CKD) and its complications. Integrating these practices can significantly lessen the environmental impact of nephrology.

PURPOSE OF REVIEW

The aim of this study is to discuss the bidirectional relationship of climate change and kidney disease and the impact of nephrology on climate change and to discuss potential solutions.

RECENT FINDINGS

Each dialysis session consumes significant amounts of resource; reusing them will aid the environment. Plant-based diets slow renal disease and have a lower carbon footprint, making them ecologically friendly.

SUMMARY

Climate change is a growing threat to population health and healthcare. Rising temperatures raise the risk of kidney problems. Dialysis treatments also impact the environment through its high resource requirements while generating high volumes of waste and greenhouse gases. Opportunities exist to reduce the environmental impact of dialysis treatments. Plant-based diets serve to benefit both kidney disease and the environment.

US Adults' Perceptions, Beliefs, and Behaviors towards Plant-Rich Dietary Patterns and Practices: International Food Information Council Food and Health Survey Insights, 2012-2022

Expert groups recommend that populations adopt dietary patterns higher in whole, plant-based foods and lower in red and processed meat as a high-impact climate action. Yet, there is limited understanding of populations' willingness to adopt plant-rich dietary patterns. This study examined United States (US) adults' perceptions, beliefs, and behaviors towards plant-rich dietary patterns and practices over a decade. Fifteen questions from the International Food Information Council's Food and Health Surveys (2012-2022) were analyzed across four sustainability domains (i.e., human health, environmental, social, and economic domains). Most respondents had favorable perceptions of environmentally sustainable food and beverages, but sustainability influenced less than half of consumers' purchase decisions. Plant-rich dietary pattern adherence increased across survey years (12.1% [2019] to 25.8% [2022], p < 0.001). One-quarter (28.1%) of Americans reported reducing their red meat intake over 12 months (2020-2022). Yet, another 15.5% reported greater red meat intake, and 18.8% reported greater plant-based meat alternative (PBMA) intake over 12 months. The percentage of respondents who reported greater red meat and PBMA consumption in the previous 12 months significantly increased across the years surveyed (2020-2022, p < 0.05). IFIC Survey findings highlight growing US consumer awareness of health, environmental, and social sustainability but low adoption of plant-rich dietary patterns and practices. Government leadership and coordinated actions by health professionals, civil society, and businesses are needed to educate and incentivize Americans to adopt plant-rich dietary behaviors, and greater industry transparency is needed to show how food and beverage products support human and planetary health.

Commercial weight-loss diets, greenhouse gas emissions and freshwater consumption

BACKGROUND

Weight-loss attempts are widespread in the United States, with many using commercial weight-loss diet plans for guidance and support. Accordingly, dietary suggestions within these plans influence the nation's food-related environmental footprint.

METHODS

We modelled United States (US) per capita greenhouse gas emissions (GHGe) and water footprints associated with seven commercial weight-loss diets, the US baseline, and selected other dietary patterns. We characterised consumption in commercial weight-loss diets both via modelling from provided guidelines and based on specific foods in 1-week meal plans. Cradle-to-farmgate GHGe and water footprints were assessed using a previously developed model. GHGe results were compared to the EAT-Lancet 2050 target. Water footprints were compared to the US baseline.

RESULTS

Weight-loss diets had GHGe footprints on average 4.4 times the EAT-Lancet target recommended for planetary health (range: 2.4-8.5 times). Bovine meat was by far the largest contributor of GHGe in most diets that included it. Three commercial diets had water footprints above the US baseline. Low caloric intake in some diets compensated for the relative increases in GHGe- and water-intensive foods.

CONCLUSIONS

Dietary patterns suggested by marketing materials and guidelines from commercial weight-loss diets can have high GHGe and water footprints, particularly if caloric limits are exceeded. Commercial diet plan guidance can be altered to support planetary and individual health, including describing what dietary patterns can jointly support environmental sustainability and weight loss.

Aligning Environmental Sustainability, Health Outcomes, and Affordability in Diet Quality: A Systematic Review

Improving diet quality while simultaneously maintaining planetary health is of critical interest globally. Despite the shared motivation, advancement remains slow, and the research community continues to operate in silos, focusing on certain pairings (diet-climate), or with a discipline-specific lens of a sustainable diet, rather than examining their totality. This review aimed to summarize the literature on adherence to a priori defined dietary patterns in consideration of diet quality, metabolic risk factors for noncommunicable diseases (NCDs), environmental impacts, and affordability. A methodology using PRISMA guidelines was followed, and searches were performed in 7 databases as of October 2022. The Appraisal tool for Cross-Sectional Studies (AXIS) and the National Institutes of Health (NIH) quality assessment tool for observational cohort studies were employed for quality appraisal. The evidence was narratively synthesized according to the characteristics of the diet quality metrics. The review includes 24 studies published between 2017-2023. Thirteen distinct diet quality scores were identified, with those measuring adherence to national dietary guidelines the most reported. Thirteen distinct environmental impact indicators were identified, with greenhouse gas emissions (n=23) reported most. All studies reported on body mass index, and 7 studies assessed the cost of adherence. Our results are consistent with previous findings that healthier diets can reduce environmental impacts; however, incongruities between population and planetary health can occur. Hence, the "sustainability" of dietary patterns is dependent on the choice of indicators selected. Further, healthy, lower impact diets can increase financial cost, but may also provide a protective role against the risk of obesity. Given the Global Syndemic, strategies to reduce obesity prevalence should emphasize the win-win opportunities for population and planetary health through dietary change. Research should identify diets that address multiple environmental concerns to curtail burdens potentially transferring, and harmonize this with sociocultural and equity dimensions. This review was registered at PROSPERO as CRD42021238055.

Forced labour risk is pervasive in the US land-based food supply

Social risk assessments and case studies of labour conditions in food production primarily focus on specific subpopulations, regions and commodities. To date, research has not systematically assessed labour conditions against international standards across diverse, complex food products. Here we combine data on production, trade, labour intensity and qualitative risk coding to quantitatively assess the risk of forced labour embedded in the US land-based food supply, building on our previous assessment of fruits and vegetables. We demonstrate that animal-based proteins, processed fruits and vegetables, and discretionary foods are major contributors to forced labour risk and that 62% of total forced labour risk stems from domestic production or processing. Our findings reveal the widespread risk of forced labour present in the US food supply and the necessity of collaborative action across all countries-high, middle and low income-to eliminate reliance on labour exploitation.

Plant to animal protein ratio in the diet: nutrient adequacy, long-term health and environmental pressure

Background

Animal and plant protein sources have contrasting relationships with nutrient adequacy and long-term health, and their adequate ratio is highly debated.

Objective

We aimed to explore how the percentage of plant protein in the diet (%PP) relates to nutrient adequacy and long-term health but also to environmental pressures, to determine the adequate and potentially optimal %PP values.

Methods

Observed diets were extracted from the dietary intakes of French adults (INCA3, n = 1,125). Using reference values for nutrients and disease burden risks for foods, we modeled diets with graded %PP values that simultaneously ensure nutrient adequacy, minimize long-term health risks and preserve at best dietary habits. This multi-criteria diet optimization was conducted in a hierarchical manner, giving priority to long-term health over diet proximity, under the constraints of ensuring nutrient adequacy and food cultural acceptability. We explored the tensions between objectives and identified the most critical nutrients and influential constraints by sensitivity analysis. Finally, environmental pressures related to the modeled diets were estimated using the AGRIBALYSE database.

Results

We find that nutrient-adequate diets must fall within the ~15-80% %PP range, a slightly wider range being nevertheless identifiable by waiving the food acceptability constraints. Fully healthy diets, also achieving the minimum-risk exposure levels for both unhealthy and healthy foods, must fall within the 25-70% %PP range. All of these healthy diets were very distant from current typical diet. Those with higher %PP had lower environmental impacts, notably on climate change and land use, while being as far from current diet.

Conclusion

There is no single optimal %PP value when considering only nutrition and health, but high %PP diets are more sustainable. For %PP > 80%, nutrient fortification/supplementation and/or new foods are required.

Personal, behavioural and socio-environmental correlates of emerging adults' sustainable food consumption in a cross-sectional analysis

OBJECTIVE

Describe how dietary intake patterns of US young adults align with the EAT-Lancet Planetary Health Diet (PHD) sustainable diet goals and identify personal, behavioural, and socio-environmental correlates of sustainable intake.

DESIGN

Data on past-year dietary intake were captured using a FFQ. The PHD was applied to specific food groups, and a total PHD score was calculated. Linear regression models were used to identify associations between personal, behavioural and socio-environmental factors and PHD scores.

SETTING

This cross-sectional analysis uses data from the second wave of EAT 2010-2018 (Eating and Activity over Time), a population-based longitudinal study recruited in Minnesota.

PARTICIPANTS

Ethnically/racially diverse group of participants (n 1308) with a mean age of 22·1 (sd 2·0) years.

RESULTS

The mean PHD score was 4·1 (sd 1·4) on a scale of 0-14, with 14 representing the most sustainable. On average, participants consumed fewer whole grains, fish, legumes, soya, and nuts than ideal for a sustainable diet, and an excess of eggs, added sugar, and meat. The PHD score was higher for participants with higher socio-economic status (SES) and greater educational attainment. Higher home availability of healthy food (β = 0·24, P < 0·001) and less frequent fast-food consumption (β = -0·26, P < 0·001) were the strongest correlates of PHD scores.

CONCLUSIONS

Results suggest that a high percentage of participants may not be achieving the sustainable diet goals defined by the PHD. Reductions in meat consumption and increases in plant-based foods are necessary to increase the sustainability of US young adults' diets.

Greenhouse gas emissions, cost, and diet quality of specific diet patterns in the United States

BACKGROUND

Major policy agendas are calling for accelerated investment in research that addresses the impact of diet patterns on multiple domains of sustainability.

OBJECTIVE

To evaluate the comparative greenhouse gas emissions, diet cost, and diet quality of plant-based, low grain, restricted carbohydrate, low fat, and time restricted diet patterns on a daily per capita basis.

DESIGN

Dietary data from the National Health and Nutrition Examination Survey (2013-2016, n=4,025) were merged with data on greenhouse gas emissions (GHGE) and food prices from multiple databases. The Healthy Eating Index-2015 was used to measure diet quality.

RESULTS

The plant-based diet pattern had the lowest GHGE (3.5 kg CO2eq, 95% CI: 3.3, 3.8 kg CO2eq) and among the lowest diet cost ($11.51, 95% CI: $10.67, $12.41), but diet quality (45.8, 95% CI: 43.3, 48.5) was similar (P>0.005) to most other diet patterns. All of the sustainability impacts of the low grain diet pattern were intermediate. The restricted carbohydrate diet pattern had the highest diet cost ($18.46, 95% CI: $17.80, $19.13) but intermediate diet quality (46.8, 95% CI: 45.7, 47.9) and moderate-to-high GHGE (5.7 kg CO2eq, 95% CI: 5.4, 5.9 kg CO2eq). The low fat diet pattern had the highest diet quality (52.0, 95% CI: 50.8, 53.1) and intermediate GHGE (4.4 kg CO2eq, 95% CI: 4.1, 4.6 kg CO2eq) and diet cost ($14.53, 95% CI: $13.73, $15.38). The time restricted diet pattern had among the lowest diet quality score (42.6, 95% CI: 40.8, 44.6), had GHGE similar to most other diet patterns (4.6 kg CO2eq, 95% CI: 4.2, 5.0 kg CO2eq), and low-to-moderate diet cost ($12.34, 95% CI: $11.38, $13.40).

CONCLUSIONS

Most diet patterns were associated with sustainability trade-offs. The nature of those trade-offs can help inform discussions on food and nutrition policy in the US, including the National Strategy on Hunger, Nutrition, and Health, and future Dietary Guidelines for Americans.

Research needs for a food system transition

The global food system, and animal agriculture in particular, is a major and growing contributor to climate change, land system change, biodiversity loss, water consumption and contamination, and environmental pollution. The copious production and consumption of animal products are also contributing to increasingly negative public health outcomes, particularly in wealthy and rapidly industrializing countries, and result in the slaughter of trillions of animals each year. These impacts are motivating calls for reduced reliance on animal-based products and increased use of replacement plant-based products. However, our understanding of how the production and consumption of animal products, as well as plant-based alternatives, interact with important dimensions of human and environment systems is incomplete across space and time. This inhibits comprehensively envisioning global and regional food system transitions and planning to manage the costs and synergies thereof. We therefore propose a cross-disciplinary research agenda on future target-based scenarios for food system transformation that has at its core three main activities: (1) data collection and analysis at the intersection of animal agriculture, the environment, and societal well-being, (2) the construction of target-based scenarios for animal products informed by these new data and empirical understandings, and (3) the evaluation of impacts, unintended consequences, co-benefits, and trade-offs of these target-based scenarios to help inform decision-making.

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.

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.

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.

Heartfulness in Vegans, Vegetarians, and Omnivores

BACKGROUND

The primary goal of this study was to investigate the relation between the choice of a vegan or vegetarian diet as a criterion of sustainability and the aspect of heartfulness. We also analyzed which demographic, diet-related, and mindfulness practice-related variables could predict the different facets of heartfulness.

METHODS

In total, 419 persons participated. After providing demographic, diet-related, and mindfulness practice-related information, participants completed a gratitude questionnaire, a self-compassion scale, a compassion scale, and an equanimity scale.

RESULTS

The results show that vegans and vegetarians indicated higher scores than omnivores in some aspects of heartfulness, such as both self-compassion scales. These effects could not be shown for the two equanimity scales and for the gratitude questionnaire. Most aspects of heartfulness could either be predicted by demographic or diet-related variables. The best predictors of the elements of heartfulness were the ecological, ethical, or health-related reasons for choosing their diet stated by the participants, as well as the importance the participants attached to nutrition.

CONCLUSION

This study provides evidence that vegans and vegetarians scored higher in several aspects of heartfulness. Vegans tended to score even higher than vegetarians. Both demographic and diet-related variables could predict heartfulness.

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.

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

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

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Global food systems transitions have enabled affordable diets but had less favourable outcomes for nutrition, environmental health, inclusion and equity

Over the past 50 years, food systems worldwide have shifted from predominantly rural to industrialized and consolidated systems, with impacts on diets, nutrition and health, livelihoods, and environmental sustainability. We explore the potential for sustainable and equitable food system transformation (ideal state of change) by comparing countries at different stages of food system transition (changes) using food system typologies. Historically, incomes have risen faster than food prices as countries have industrialized, enabling a simultaneous increase in the supply and affordability of many nutritious foods. These shifts are illustrated across five food system typologies, from rural and traditional to industrial and consolidated. Evolving rural economies, urbanization and changes in food value chains have accompanied these transitions, leading to changes in land distribution, a smaller share of agri-food system workers in the economy and changes in diets. We show that the affordability of a recommended diet has improved over time, but food systems of all types are falling short of delivering optimal nutrition and health outcomes, environmental sustainability, and inclusion and equity for all. Six ‘outlier’ case studies (Tajikistan, Egypt, Albania, Ecuador, Bolivia and the United States of America) illustrate broad trends, trade-offs and deviations. With the integrated view afforded by typologies, we consider how sustainable transitions can be achieved going forward.

Associations of Dyslipidemia with Dietary Intakes, Body Weight Status and Sociodemographic Factors among Adults in the United Arab Emirates

Research on dietary and other factors associated with dyslipidemia in the United Arab Emirates (UAE) is limited. This study assessed the association of diet, body weight and other risk factors of dyslipidemia by conducting a cross-sectional survey among adults residing in three emirates of the UAE. Validated quantitative food frequency questionnaire and the WHO STEPS Instrument were used to assess dietary intakes, body weight and dyslipidemia-related diagnosis. Composite Mediterranean Diet Score was used to assess adherence to the Mediterranean Diet (MD). Of the 610 participants, dyslipidemia was reported by 23.5% of the 319 participants who ever had blood cholesterol levels measured. Self-reported dyslipidemia was associated with increased age, higher BMI, diabetes, hypertension and cardiovascular disease. Most participants did not meet the recommendations for dietary fiber and calorie intake from saturated fats (61.3% and 81.2%, respectively). Participants with dyslipidemia reported a higher median daily intake of vegetables compared to those without dyslipidemia (p < 0.001), who also showed a significantly higher intake of refined grains and sugar-sweetened beverages (p = 0.008). Participants aged ≥50 years were more likely to have adhered to the MD compared to 18−30-year old participants (OR = 4.16; 95% CI 2.59−6.69). Non-Emiratis had higher odds of adherence to the MD compared to UAE nationals (OR = 1.46; 95%CI 1.04−2.06). Interventions targeting behavioral risk factors of dyslipidemia are warranted.

Transitioning to sustainable healthy diets: A model-based and conceptual system thinking approach to optimized sustainable diet concepts in the United States

Food production and consumption are essential in human existence, yet they are implicated in the high occurrences of preventable chronic diseases and environmental degradation. Although healthy food may not necessarily be sustainable and vice versa, there is an opportunity to make our food both healthy and sustainable. Attempts have been made to conceptualize how sustainable healthy food may be produced and consumed; however, available data suggest a rise in the prevalence of health-related and negative environmental consequences of our food supply. Thus, the transition from conceptual frameworks to implementing these concepts has not always been effective. This paper explores the relative environmental and health risks associated with highly consumed food groups and develops a methodological workflow for evaluating the sustainability of diet concepts in the context of different health, socio-economic and environmental indicators. In addition, we apply the multi-criteria decision-making techniques (an integrated Analytic Hierarchy Process- Technique for order preference by similarity to ideal solution (AHP-TOPSIS) model) to examine the health and environmental impact of selected sustainable healthy diet concepts implemented in the United States. The principal findings indicate that adopting plant-based diet patterns would benefit the environment and the population's health. However, the up-scale, broad adoption and implementation of these concepts are hindered by critical bottlenecks. Hence we propose potential modification strategies through a conceptual system thinking approach to deliver optimized sustainable diet concepts to aid in the realization of the anticipated benefits of adoption/implementation.

The cost of healthier and more sustainable food choices: Do plant-based consumers spend more on food?

Plant-based diets are often promoted as healthier and more sustainable and thus as a mechanism to achieve the targets proposed to mitigate climate change and noncommunicable diseases. However, plant-based diets can be perceived as more expensive than the common omnivorous diets, when considering the expensive novel meat substitutes and also the higher costs of fruits and vegetables, whose consumption is perceived to increase. Therefore, the present study assesses the question: Do plant-based consumers spend more on food compared to omnivorous consumers? Based on primary data (n = 1040) collected through an online survey, representative of the Portuguese population, through logistic regressions, it was possible to conclude that plant-based consumers, particularly vegan, are associated with lower food expenditures compared to omnivorous consumers. In fact, plant-based consumers are shown to spend less than all other consumers assessed. Food policies aligning healthiness and sustainability with affordability can deliver a major boost for the promotion of plant-based diets and help achieve the mitigation targets proposed.

Diet Sustainability Analyses Can Be Improved With Updates to the Food Commodity Intake Database

Diet sustainability analyses inform policymaking decisions and provide clinicians and consumers with evidence-based information to make dietary changes. In the United States, the Food Commodity Intake Database (FCID) provides a crosswalk for integrating nationally representative data on food intake from the National Health and Nutrition Examination Survey (NHANES) with data on sustainability outcomes from other publicly available databases. However, FCID has not been updated since 2010 and does not link with contemporary NHANES data, which limits further advancements in sustainability research. This study fills this research gap by establishing novel linkages between FCID and NHANES 2011-2018, comparing daily per capita food intake with and without these linkages, and making these data publicly available for use by other researchers. To update FCID, two investigators independently established novel data linkages, a third investigator resolved discrepancies, and a fourth investigator audited linkages for accuracy. Dietary data were acquired from nearly 45,000 adults from 2001 to 2018, and food intake was compared between updated vs. non-updated FCID versions. Total food intake from 2011 to 2018 was 5-23% higher using the updated FCID compared to the non-updated version, and intake was over 100% higher in some years for some food categories including poultry, eggs, legumes, starchy vegetables, and tropical oils (P < 0.001 for all comparisons). Further efforts may be needed to create new food composition data to reflect new products and reformulations that enter the food supply over time. This study removes a barrier to further diet sustainability analyses by establishing a data crosswalk between contemporary NHANES and other publicly available databases on agricultural resource use, environmental impacts, and consumer food expenditures.

Healthy U.S.-style dietary patterns can be modified to provide increased energy from protein

Background

Dietary patterns developed by the USDA provide modest levels of protein (14–18% energy) within the Acceptable Macronutrient Distribution Range (AMDR) of 10–35% for adults, though diets providing a higher percentage of energy may be beneficial for some individuals. The purpose of this study was to determine if it is feasible to modify the Healthy U.S.-Style Eating Pattern (“HEP”) to provide a higher percentage of energy from protein.

Methods

Using the framework implemented by the USDA in developing the HEP, energy from protein was set at 20%, 25%, and 30%. Amounts of protein foods were proportionally increased while amounts of other foods were adjusted iteratively within specified parameters. The models also disaggregated total meat/poultry into fresh and processed forms to develop patterns maintaining current proportions, current levels, reduced, or no processed meat/poultry. Nutrient intakes were compared with nutrient goals for representative U.S. populations with 2,000 kcal needs (females 19–30 years, males 51–70 years), with 90% of the Recommended Dietary Allowance or Adequate Intake regarded as sufficient.

Results

Dietary patterns with 20% energy from protein were constructed with minor deviations from the current 2,000 kcal HEP. Dietary patterns with 25% energy from protein were constructed for all levels of processed meat/poultry excluding the current proportion model, though relative to the current HEP the constructed patterns reflect substantial reductions in amounts of refined grains and starchy vegetables, and substantial increases in protein foods consumed as beans and peas, seafood, and soy products. It was not possible to develop a pattern with 30% energy from protein without reducing the percentage of energy from carbohydrate below the AMDR or non-compliance with other modeling constraints. Stepwise reductions in processed meat/poultry reduced sodium intake.

Conclusions

It is feasible to develop dietary patterns in a 2,000 kcal diet while mirroring the HEP that meet recommended intakes of nutrients with 20% or 25% energy from protein, though the pattern with 25% energy from protein may be more idealistic than realistic. Reduced levels of processed meat/poultry may translate to lower sodium intake.

Sustainability of Diets in Mexico: Diet Quality, Environmental Footprint, Diet Cost, and Sociodemographic Factors

Background

Little is known about the current intake of sustainable diets globally and specifically in middle-income countries, considering nutritional, environmental and economic factors.

Objective

To assess and characterize the sustainability of Mexican diets and their association with sociodemographic factors.

Design

Dietary data of 2,438 adults within the National Health and Nutrition Survey 2012 by integrating diet quality measured by the Healthy Eating Index (HEI-2015), diet cost, and four environmental indicators were analyzed: land use (LU), biodiversity loss (BDL), carbon footprint (CFP), and blue water footprint (BWFP). We defined healthier more sustainable diets (MSD) as those with HEI-2015 above the overall median, and diet cost and environmental indicators below the median. Logistic regression was used to evaluate the association of sociodemographic factors with MSD.

Results

MSD were consumed by 10.2% of adults (4% of urban and 22% of rural), who had lower intake of animal-source foods, unhealthy foods (refined grains, added sugar and fats, mixed processed dishes and sweetened beverages), fruits, and vegetables, and higher intake of whole grains than non-MSD subjects. Characteristics of MSD vs. non-MSD (urban; rural) were: HEI-2015 (62.6 vs. 51.9; 66.8 vs. 57.6), diet-cost (1.9 vs. 2.8; 1.9 vs. 2.5 USD), LU (3.3 vs. 6.6; 3.2 vs. 5.9 m²), BDL (105 vs. 780; 87 vs. 586 species × 10⁻¹⁰), BWFP (244 vs. 403; 244 vs. 391 L), and CFP (1.6 vs. 4.4; 1.6 vs. 3.7 kg CO₂eq). Adults from rural vs. urban (OR 2.7; 95% CI: 1.7, 4.1), or from the South (OR 2.1; 95% CI: 1.1, 3.9), Center (OR 2.3; 95% CI: 1.3, 4.4) vs. the North were more likely to consume MSD, while adults with high vs. low socioeconomic status were less likely (OR 0.17; 95% CI: 0.09, 0.3).

Conclusions

The MSD is a realistic diet pattern mainly found in disadvantaged populations, but diet quality is still sub-optimal. Increased consumption of legumes, fruits, and vegetables, and a reduction in unhealthy foods, is required to improve nutritional quality of diets while ensuring their environmental sustainability.

Relationship Between Dietary Patterns and Chronic Diseases in Rural Population: Management Plays an Important Role in the Link

Objective

Health dietary pattern is related with reduced risk of chronic metabolic disease, but the benefits were not fully clear in the Chinese population. The aim of this study was to explore the association between dietary patterns and multiple chronic metabolic diseases in middle-aged and elderly Chinese.

Methods

A total of 718 Chinese adults aged ≥ 45 who lived in the Huairou regions of Beijing were included in the present cross-sectional analysis from 2019 to 2020. Dietary data were obtained by food frequency questionnaires (FFQs). Dietary patterns were identified by principal components analysis (PCA). Logistic regression analysis and hierarchical analysis were used to examine the relationship among dietary patterns, health management, and chronic diseases.

Results

Five dietary patterns were discovered in the subjects. The pattern with the higher percentage of energy supply by lipid was a risk factor for hypertension [odds ratio (OR) = 2.067, p = 0.013]. Lower energy intake (OR = 0.512, p = 0.012) and a reasonable ratio of dietary energy supply (OR = 0.506, p = 0.011) were beneficial to diabetes. The substitution of potato for grain might be an effective way of reducing diabetes (OR = 0.372, p &lt; 0.001). The higher intake of high-quality protein was the protective factor for coronary heart disease (CHD; OR = 0.438, p = 0.008). Moderate intervention (OR = 0.185, p = 0.033) and appropriate health education (OR = 0.432, p = 0.016) could greatly subserve the prevention of chronic diseases, especially for hyperlipidemia. Men were more likely to be affected by health education, intervention, and follow-up than women. The prevalence of multimorbidity was higher in women (43.2%) than men (41.5%). The staple food intake and health management were also important factors to prevent multimorbidity.

Conclusion

Dietary pattern with appropriate energy intake, a reasonable source of energy supply, high quality of macronutrients, and moderate management was associated with decreased risk of chronic metabolic diseases. Further studies are needed to clarify the cause–effect relationship between dietary patterns, health management, and chronic diseases and give suggestions to chronic metabolic disease prevention in middle-aged and elderly people in a rural area.

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.

Cooking at Home, Fast Food, Meat Consumption, and Dietary Carbon Footprint among US Adults

Shifting consumer behavior towards more sustainable diets can benefit environmental sustainability and human health. Although more frequent home cooking is associated with a better diet quality and fast-food consumption with worse diet quality, the environmental impact of diets based on frequency of cooking or eating fast food is not well understood. The objective of this study was to investigate whether the frequency of cooking dinner at home or eating fast food is associated with dietary greenhouse gas emissions (GHGE). We linked 24-h dietary recall data from adult respondents in the 2007-2010 National Health and Nutrition Examination Survey (NHANES) (N = 11,469) to a database of GHGE factors to obtain a measure of dietary GHGE (kgCO2-eq/2000 kcal) (the sum of emissions released in the production of food for an individual's diet), adjusted by energy intake (kgCO2-eq/2000 kcal). We examined associations between frequency of cooking dinner (the only meal for which cooking frequency was measured), frequency of eating fast food, and dietary GHGE and protein sources (beef, pork, poultry, other meat, and fish and seafood (g/2000 kcal)) using generalized linearized regression models that controlled for age, sex, and other socio-economic characteristics. Greater cooking frequency was associated with higher dietary GHGE. In fully adjusted models, cooking 5-6 times/week was associated with an additional 0.058 kgCO2-eq/2000 kcal (SE 0.033) and cooking 7 times/week was associated with an additional 0.057 kgCO2-eq/2000 kcal (SE 0.027) when compared to cooking 0-2 times/week. Individuals in households who cooked dinner more frequently consumed significantly more meat, poultry, and fish (cooking 7 times/week: 148.7 g/2000 kcal vs. cooking 0-2 times/week: 135.4 g/2000 kcal, p-trend = 0.005), which could explain the association with a higher carbon footprint diet. There were few associations of note between fast-food frequency and GHGE. Policies and interventions that reduce consumption of meat and increase consumption of plants when both cooking meals at home and eating meals out are needed to shift toward diets that will be beneficial for both human health and the health of the planet.

Assessment of the Methodology That Is Used to Determine the Nutritional Sustainability of the Mediterranean Diet-A Scoping Review

Mediterranean diet (MedDiet) is often used as an example of a sustainable diet that promotes a sustainable food system. MedDiet presents low environmental impacts, is characterized by high sociocultural food values, allows for positive local economic returns, and presents major health and nutrition benefits. Previous studies have not systematically examined the methodological assessment of MedDiet nutritional sustainability. In our study, we review the methodological assessment of nutritional sustainability, filling a crucial gap in the literature that can inform the state of the art regarding the cross-disciplinary assessment of MedDiet nutritional sustainability. Through a systematic search on PubMed and Scopus, we identified 28 studies, published between 2013 and 2021, that dealt with the MedDiet nutritional sustainability. Studies that assessed the sustainability of MedDiet based on dietary consumption data, studies that explored the MedDiet sustainability resorting to dietary scenarios, and studies with a mixed approach (dietary consumption and dietary scenarios) and proposals of methodological approaches to assess the MedDiet nutritional sustainability were summarized. We identified 24 studies exploring the dimensions of nutritional sustainability of the MedDiet, and 4 proposing the methodological approaches to assess the MedDiet nutritional sustainability or the sustainability of MedDiet typical agro-foods. From the 24 studies exploring the sustainability of MedDiet, none fully addressed the complexity of the four dimensions of nutritional sustainability (environmental, economic, socio-cultural, and health-nutrition). One of the methodological proposals to assess the MedDiet nutritional sustainability contemplated on the four dimensions of nutritional sustainability, as well as one of the methodological proposals to assess the sustainability of typical agro-foods of MedDiet. Environmental sustainability was the most well-studied dimension, while no study focuses on the socio-cultural dimension of sustainability. Our study reviewed for the first time the assessment of nutritional sustainability of MedDiet. To the best of our knowledge, no research has been made assessing MedDiet in all the dimensions of the complex concept, that is nutritional sustainability. Integrating health and nutrition, environmental, economic, and socio-cultural considerations across scales and contexts can offer a more complete understanding of the opportunities and barriers to achieving nutritional sustainability not only in MedDiet but also in other dietary patterns and food products.

An Alternative Nutrient Rich Food Index (NRF-ai) Incorporating Prevalence of Inadequate and Excessive Nutrient Intake

Most nutrient profiling models give equal weight to nutrients irrespective of their ubiquity in the food system. There is also a degree of arbitrariness about which nutrients are included. In this study, an alternative Nutrient Rich Food index was developed (NRF-ai, where ai denotes adequate intake) incorporating prevalence of inadequate and excessive nutrient intake among Australian adults. Weighting factors for individual nutrients were based on a distance-to-target method using data from the Australian Health Survey describing the proportion of the population with usual intake less than the Estimated Average Requirement defined by the Nutrient Reference Values for Australia and New Zealand. All nutrients for which data were available were included, avoiding judgements about which nutrients to include, although some nutrients received little weight. Separate models were developed for females and males and for selected age groups, reflecting differences in nutrient requirements and usual intake. Application of the new nutrient profiling models is demonstrated for selected dairy products and alternatives, protein-rich foods, and discretionary foods. This approach emphasises the need to identify foods that are rich in those specific nutrients for which intake is below recommended levels and can be used to address specific nutrient gaps in subgroups such as older adults. In addition, the new nutrient profiling model is used to explore other sustainability aspects, including affordability (NRF-ai per AUD) and ecoefficiency (NRF-ai/environmental impact score).

Perspective: Unpacking the Wicked Challenges for Alternative Proteins in the United States: Can Highly Processed Plant-Based and Cell-Cultured Food and Beverage Products Support Healthy and Sustainable Diets and Food Systems?

Over the past decade, a plethora of alternative protein (AP) products has entered the US food system as plant-based food and beverage products. These AP products, which include plant-based meat and dairy alternatives and cell-cultured meat and seafood products, are being developed for the marketplace to simulate the appearance, texture, taste, and flavor and nutritional profiles of animal products. The new generation of AP plant-based and cell-cultured food and beverage products are part of a market-driven narrative that has embraced technology to address future human health, environmental, ethical, and planetary health challenges. This perspective article synthesizes evidence about the benefits of adopting minimally processed plant-based diets that support sustainable food systems and human and planetary health. Thereafter, it examines 4 wicked challenges related to AP products in the US context that include 1) a confusing marketing landscape for the public; 2) diverse views and varying acceptance among consumers about the health and environmental benefits of these products; 3) inadequate education and labeling provided by federal agencies to enable consumers to understand how these may support healthy sustainable diets; and 4) slow federal policy and regulatory actions to address the range of AP products and provide industry guidance. The article concludes with suggested policies and actions for government agencies and food system actors to address these challenges. Future research and actions are needed to balance the human health, equity, animal welfare, and economic viability goals and to clarify how AP products may support safe, healthy, sustainable diets and food systems.

Small targeted dietary changes can yield substantial gains for human health and the environment

To identify environmentally sustainable foods that promote health, we combined nutritional health-based and 18 environmental indicators to evaluate, classify and prioritize individual foods. Specifically for nutrition, we developed the Health Nutritional Index to quantify marginal health effects in minutes of healthy life gained or lost of 5,853 foods in the US diet, ranging from 74 min lost to 80 min gained per serving. Environmental impacts showed large variations and were found to be correlated with global warming, except those related to water use. Our analysis also indicated that substituting only 10% of daily caloric intake from beef and processed meat for fruits, vegetables, nuts, legumes and selected seafood could offer substantial health improvements of 48 min gained per person per day and a 33% reduction in dietary carbon footprint.

Data Integration for Diet Sustainability Analyses

Diet sustainability analyses are stronger when they incorporate multiple food systems domains, disciplines, scales, and time/space dimensions into a common modeling framework. Few analyses do this well: there are large gaps in food systems data in many regions, accessing private and some public data can be difficult, and there are analytical challenges, such as creating linkages across datasets and using complex analytical methods. This article summarizes key data sources across multiple domains of food system sustainability (nutrition, economic, environment) and describes methods and tools for integrating them into a common analytic framework. Our focus is the United States because of the large number of publicly available and highly disaggregated datasets. Thematically, we focus on linkages that exist between environmental and economic datasets to nutrition, which can be used to estimate the cost and agricultural resource use of food waste, interrelationships between healthy eating and climate impacts, diets optimized for cost, nutrition, and environmental impacts, and others. The limitations of these approaches and data sources are described next. By enhancing data integration across these fields, researchers can be better equipped to promote policy for sustainable diets.

Eat Well to Fight Obesity… and Save Water: The Water Footprint of Different Diets and Caloric Intake and Its Relationship With Adiposity

Water scarcity and excess adiposity are two of the main problems worldwide and in Mexico, which is the most obese country in the world and suffers from water scarcity. Food production represents 90% of a person's water footprint (WF), and healthy diets can lead to less WF than do unhealthy diets related to obesity. We calculated the WF of the diet and caloric intake of adults in Mexico and analyzed its relationship with adiposity. Also, the risk of water expenditure due to adiposity and adherence to dietary recommendations regarding WF of international healthy diets were examined. A Food Consumption Frequency Questionnaire (FCFQ) was applied to 395 adults. Body mass index (BMI), associated with adiposity indicators, was used as a reference for grouping a sample into adiposity levels. The WF was calculated according to the WF Assessment Method, considering correction factors and accounting for water involved in cooking and food washing. Our results showed that the Mexican diet spends 6,056 liters per person per day (L p-1d-1) and is 55% higher than international healthy diets WF. Consumption of beef, milk, fruits, chicken, and fatty cereals represented 56% of total WF. Strong relations appeared between hypercaloric diets and high WF. Diets of people with excess adiposity generated statistically higher WF with extra expenses of 729 L p-1d-1 compared with the normal adiposity population. Following nutritional recommendations offers a protective factor in water care, whereas not adhering to these represents a risk up to 93 times greater of water expenditure regarding international healthy diets. Therefore, both for the general population and to regulate obesity, adequate diets can help mitigate the problem of water scarcity.

Nutritional quality and carbon footprint of university students' diets: results from the EHU12/24 study

Objective:

To evaluate diets in terms of nutritional characteristics and quality from the perspectives of health, greenhouse gas emissions (GHGE) and possible associations with each other in a representative sample of students at a public university.

Design:

Cross-sectional. Dietary intake was evaluated with a validated FFQ, and diet quality was assessed through the Healthy Eating Index (HEI-2010) and MedDietScore (MDS). GHGE data were obtained from the literature. In addition, sex, socio-economic status (SES) and body fat (BF) status were analysed as covariates.

Setting:

Basque Autonomous Community, Spain.

Participants:

Totally, 26 165 healthy adults aged 18–28 years.

Results:

Student diets were characterised by low consumption of carbohydrates (38·72 % of total energy intake (TEI)) and a high intake of lipids (39·08 % of TEI). Over half of the participants had low dietary quality. The low-emitting diets were more likely to be consumed by subjects with low HEI-2010 scores (β: 0·039 kg eCO₂/1000 kcal/d) and high MDS scores (β: −0·023 kg eCO₂/1000 kcal/d), after controlling for sex, SES and BF status. Both the low-emitting and healthy diets were more likely to be consumed by women and by those with normal BF percentage.

Conclusions:

UPV/EHU university students’ diets were characterised by moderate quality from a nutritional perspective and moderate variation in the size of carbon footprints. In this population, diets of the highest quality were not always those with the lowest diet-related GHGE; this relationship depended in part on the constructs and scoring criteria of diet quality indices used.

Nutrient Composition of a Selection of Plant-Based Ground Beef Alternative Products Available in the United States

BACKGROUND

Sales of plant-based foods intended as direct replacements for animal products have been growing in the United States. Little is known about the nutritional quality of these products.

OBJECTIVE

Our aim was to evaluate the nutritional quality of a selection of plant-based ground beef alternative products available in the US marketplace and compare it with the nutrient content of ground beef.

DESIGN

We conducted an analysis of the food and nutrient composition information available for plant-based ground beef alternative products in the 2020 version of the University of Minnesota Nutrition Coordinating Center Food and Nutrient Database.

PARTICIPANT/SETTING

We analyzed a selection of 37 plant-based ground beef alternative products available in the United States in 2019.

MAIN OUTCOMES MEASURES

Food product content of energy, macronutrients, fatty acids, vitamins, minerals and selected additional food components was measured.

STATISTICAL ANALYSIS

The percent Daily Value (DV) per 3-ounce cooked portion of each product was determined for nutrients with a DV. The median, interquartile range (IQR), minimum, and maximum nutrient values were calculated for all products by classification as vegan and nonvegan.

RESULTS

The median saturated fat content of the plant-based ground beef alternatives products as a %DV was 4% (IQR 2%). Vitamin and minerals for which median %DV values for plant-based ground beef alternative products were 10% or higher included folate (10%, IQR 10%), niacin (21%, IQR 7%), iron (10%, IQR 5%), phosphorous (10%, IQR 4%), sodium (18%, IQR 7%), manganese (20%, IQR 20%), and copper (24%, IQR 10%). The median dietary fiber content of the plant-based ground beef alternative products was 15% of the DV (IQR 6%). Most of the products contained less protein, zinc, and vitamin B12 than ground beef.

CONCLUSIONS

The major brands of plant-based ground beef alternative products examined in this study have nutritional strengths as well as some shortcomings. Additional research to examine a broader set of plant-based meat alternative products, such as those designed as substitutes for chicken and pork, is warranted.

Perspective: Modeling Healthy Eating Patterns for Food-Based Dietary Guidelines-Scientific Concepts, Methodological Processes, Limitations, and Lessons

The relations between dietary features and human health are varied and complex. Health-related variables are many and they have intricate relations at different and interrelated nutritional levels: nutrients, food groups, and the complex overall pattern. Food-based dietary guidelines (FBDGs) are principally designed to synthesize this information to make it available to the public. Here, we describe the method used to establish healthy eating patterns (HEPs) for the latest French FBDGs, which consists of in-depth food pattern modeling using an enhanced optimization method that gathered all aspects of HEPs. We present the novelty of this food modeling approach for FBDGs, which aims to gather information related to nutrients, food contaminants, and epidemiological relations with long-term health, and to be combined with the objective of realistic dietary patterns that deviate minimally from the prevailing diet. We draw lessons from stepwise implementation of the method and discuss its strengths, limitations, and perspectives. In light of the modeled HEPs, we discuss the importance of food grouping; of accounting for dietary habits while not precluding modeled diets that can be realistic/acceptable; and of taking into account the exposure to food contaminants. We discuss the tolerance and flexibility to be applied to certain dietary reference values for nutrients and health-based guidance values for contaminants so that HEPs can ultimately be identified, and how account can be taken of varied health-related outcomes applied to food groups. Although the approach involves all the peculiar uncertainties of numerous optimization model parameters and input data, its merit is that it offers a rationalized approach to establishing HEPs with multiple constraints and competing objectives. It is also versatile because it is possible to operationalize further dimensions of dietary patterns to favor human and planetary health.

Sustainable Agri-Food Systems: Environment, Economy, Society, and Policy

Agri-food systems (AFS) have been central in the debate on sustainable development. Despite this growing interest in AFS, comprehensive analyses of the scholarly literature are hard to find. Therefore, the present systematic review delineated the contours of this growing research strand and analyzed how it relates to sustainability. A search performed on the Web of Science in January 2020 yielded 1389 documents, and 1289 were selected and underwent bibliometric and topical analyses. The topical analysis was informed by the SAFA (Sustainability Assessment of Food and Agriculture systems) approach of FAO and structured along four dimensions viz. environment, economy, society and culture, and policy and governance. The review shows an increasing interest in AFS with an exponential increase in publications number. However, the study field is north-biased and dominated by researchers and organizations from developed countries. Moreover, the analysis suggests that while environmental aspects are sufficiently addressed, social, economic, and political ones are generally overlooked. The paper ends by providing directions for future research and listing some topics to be integrated into a comprehensive, multidisciplinary agenda addressing the multifaceted (un)sustainability of AFS. It makes the case for adopting a holistic, 4-P (planet, people, profit, policy) approach in agri-food system studies.

Sustainable Diets for Cardiovascular Disease Prevention and Management

PURPOSE OF REVIEW

Healthy dietary patterns are recommended for prevention of cardiovascular disease, which remains the leading cause of morbidity and mortality globally. In this review, we discuss dietary patterns that are not only optimal for CVD prevention and management but also sustainable in maximizing health, environmental, and economic benefits.

RECENT FINDINGS

The growing literature on sustainable diets in the context of environmental sustainability includes subtopics of climate change, land use, biodiversity loss, freshwater use, and reactive nitrogen emissions. Similarly, economic sustainability, beyond the retail cost of food, extends to healthcare costs and the economic costs of environmental destruction related to current agricultural practices and food choices. Dietary patterns that are high in plant foods and low in animal foods could maximize health, environmental, and economic benefits; however, questions remain about how to best promote these patterns to achieve wider adoption in an environmentally and economically sustainable way.

Indicators and Recommendations for Assessing Sustainable Healthy Diets

Research coupling human nutrition and sustainability concerns is a rapidly developing field, which is essential to guide governments' policies. This critical and comprehensive review analyzes indicators and approaches to "sustainable healthy diets" published in the literature since this discipline's emergence a few years ago, identifying robust gauges and highlighting the flaws of the most commonly used models. The reviewed studies largely focus on one or two domains such as greenhouse gas emissions or water use, while overlooking potential impact shifts to other sectors or resources. The present study covers a comprehensive set of indicators from the health, environmental and socio-economic viewpoints. This assessment concludes that in order to identify the best food option in sustainability assessments and nutrition analysis of diets, some aspects such as the classification and disaggregation of food groups, the impacts of the rates of local food consumption and seasonality, preservation methods, agrobiodiversity and organic food and different production systems, together with consequences for low-income countries, require further analysis and consideration.

The carbon footprint of dietary guidelines around the world: a seven country modeling study

Background

Do the environmental impacts inherent in national food-based dietary guidelines (FBDG) vary around the world, and, if so, how? Most previous studies that consider this question focus on a single country or compare countries’ guidelines without controlling for differences in country-level consumption patterns. To address this gap, we model the carbon footprint of the dietary guidelines from seven different countries, examine the key contributors to this, and control for consumption differences between countries.

Methods

In this purposive sample, we obtained FBDG from national sources for Germany, India, the Netherlands, Oman, Thailand, Uruguay, and the United States. These were used to structure recommended diets using 6 food groups: protein foods, dairy, grains, fruits, vegetables, and oils/fats. To determine specific quantities of individual foods within these groups, we used data on food supplies available for human consumption for each country from the UN Food and Agriculture Organization’s food balance sheets. The greenhouse gas emissions (GHGE) used to produce the foods in these consumption patterns were linked from our own database, constructed from an exhaustive review of the life cycle assessment literature. All guidelines were scaled to a 2000-kcal diet.

Results

Daily recommended amounts of dairy foods ranged from a low of 118 ml/d for Oman to a high of 710 ml/d for the US. The GHGE associated with these two recommendations were 0.17 and 1.10 kg CO₂-eq/d, respectively. The GHGE associated with the protein food recommendations ranged from 0.03 kg CO₂-eq/d in India  to 1.84 kg CO₂-eq/d in the US, for recommended amounts of 75 g/d and 156 g/d, respectively. Overall, US recommendations had the highest carbon footprint at 3.83 kg CO₂-eq/d, 4.5 times that of the recommended diet for India, which had the smallest footprint. After controlling for country-level consumption patterns by applying the US consumption pattern to all countries, US recommendations were still the highest, 19% and 47% higher than those of the Netherlands and Germany, respectively.

Conclusions

Despite our common human biology, FBDG vary tremendously from one country to the next, as do the associated carbon footprints of these guidelines. Understanding the carbon footprints of different recommendations can assist in future decision-making to incorporate environmental sustainability in dietary guidance.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12937-021-00669-6.

The importance of food systems and the environment for nutrition

Global and local food system transformation is necessary in order to ensure the delivery of healthy, safe, and nutritious foods in both sustainable and equitable ways. Food systems are complex entities that affect diets, human health, and a range of other outcomes including economic growth, natural resource and environmental resiliency, and sociocultural factors. However, food systems contribute to and are vulnerable to ongoing climate and environmental changes that threaten their sustainability. Although there has been increased focus on this topic in recent years, many gaps in our knowledge persist on the relation between environmental factors, food systems, and nutritional outcomes. In this article, we summarize this emerging field and describe what innovative nutrition research is needed in order to bring about food policy changes in the era of climate disruption and environmental degradation.

Healthy diets can create environmental trade-offs, depending on how diet quality is measured

Background

There is an urgent need to assess the linkages between diet patterns and environmental sustainability in order to meet global targets for reducing premature mortality and improving sustainable management of natural resources. This study fills an important research gap by evaluating the relationship between incremental differences in diet quality and multiple environmental burdens, while also accounting for the separate contributions of retail losses, inedible portions, and consumer waste.

Methods

Cross sectional, nationally-representative data on food intake in the United States were acquired from the National Health and Nutrition Examination Survey (2005–2016), and were linked with nationally-representative data on food loss and waste from published literature. Survey-weighted procedures estimated daily per capita food retail loss, food waste, inedible portions, and consumed food, and were summed to represent Total Food Demand. Diet quality was measured using the Healthy Eating Index-2015 and the Alternative Healthy Eating Index-2010. Data on food intake, loss, and waste were inputted into the US Foodprint Model to estimate the amount of agricultural land, fertilizer nutrients, pesticides, and irrigation water used to produce food.

Results

This study included dietary data from 50,014 individuals aged ≥2 y. Higher diet quality (HEI-2015 and AHEI-2010) was associated with greater per capita Total Food Demand, as well as greater retail loss, inedible portions, consumer waste, and consumed food (P < 0.001 for all comparisons). Consumed food accounted for 56–74% of agricultural resource use (land, fertilizer nutrients, pesticides, and irrigation water), retail loss accounted for 4–6%, inedible portions accounted for 2–15%, and consumer waste accounted for 20–23%. Higher diet quality was associated with lower use of agricultural land, but the relationship to other agricultural resources was dependent on the tool used to measure diet quality (HEI-2015 vs. AHEI-2010).

Conclusions

Over one-quarter of the agricultural inputs used to produce Total Food Demand were attributable to edible food that was not consumed. Importantly, this study also demonstrates that the relationship between diet quality and environmental sustainability depends on how diet quality is measured. These findings have implications for the development of sustainable dietary guidelines, which requires balancing population-level nutritional needs with the environmental impacts of food choices.

Adherence to the Mediterranean Diet and Environmental Impact of the Diet on Primary School Children Living in Parma (Italy)

The key role of diet in both human health and environmental sustainability is well known. However, there is a lack of studies investigating the environmental impact of children's dietary behavior. The aim of this observational study was to investigate the dietary environmental impact in a sample of primary school children living in Parma (Italy, n = 172, 8-10 years), in relation to their adherence to the Mediterranean diet (MD). Children completed a 3-day food record in both winter and spring. Dietary records were processed to obtain: (i) adherence to the MD and (ii) mean daily carbon and ecological footprints. Adherence to the MD was similar in winter and spring, with almost half of the participants showing a medium MD score. Carbon and ecological footprints were higher during winter, and the main dietary contributors were red and processed meat for both indexes. A small positive correlation was observed between adherence to the MD and total carbon and ecological footprints. This study provided the first analysis of the relationship between adherence to the MD and environmental impact of primary school children. Further research is needed to better investigate the environmental impact of primary school children's diet and the possible relationship between the MD and environmental sustainability.