Carbon Footprint Reduction by Transitioning to a Diet Consistent with the Danish Climate-Friendly Dietary Guidelines: A Comparison of Different Carbon Footprint Databases

The MED_EAT-IT approach: A modelling study to develop feasible, sustainable and nutritionally targeted dietary patterns based on the Planetary health diet

In 2019, the EAT-Lancet Commission introduced the Planetary Health Diet (PHD), a guide for creating 2500 kcal/day country-specific sustainable diets that promote health while reducing the environmental impact associated with food systems. The PHD was previously adapted to the Italian food context, resulting in the EAT-IT dietary pattern. However, this adaptation revealed several challenges in terms of nutritional adequacy, feasibility, and environmental impact. This study reports on strategies to improve the previous pattern and align it more closely with the Mediterranean Diet, resulting in the MED_EAT-IT pattern. The study also explores feasible strategies for adapting this pattern to different energy targets, enhancing its scalability and promoting personalized approaches. For the optimization of this pattern, a specific calculation tool was developed to introduce variation to the pattern, considering realistic and feasible serving sizes and frequency of consumption. This tool integrates a defined food ontology, food composition data, and two environmental impact metrics (Carbon and Water Footprint). To optimize nutritional adequacy, several adaptations of the amount within the different food groups were made, for instance by increasing cereals and animal source by 25.5% kcal/day and 36.2% kcal/day respectively compared to EAT-IT. The resulting 2500 kcal/die pattern meets all nutritional requirements except for vitamin D and does not hamper the possibility to limit environmental impact (Carbon Footprint increased only by 12.2% but Water Footprint decreased by 6.3%). Lower energy targets were achieved by modulating amounts of the different food groups to ensure nutritional adequacy. The strategies and tools proposed here could aid in optimizing dietary plans, evaluating their potential for environmental impact reduction, and identifying issues that could hinder their adoption. Furthermore, the analyses carried out pave the way for the potential future development of new or improved foods that may contribute to the optimization of nutritional and environmental impact of diets.

Environmental impact of Norwegian self-selected diets: comparing current intake with national dietary guidelines and EAT-Lancet targets

OBJECTIVES

Dietary environmental impact in a Norwegian adult population was estimated for six environmental impact categories. Moreover, environmental benefits of scenario diets complying with the Norwegian Food-Based Dietary Guidelines (FBDG) and the EAT-Lancet reference diet were assessed.

DESIGN

The current diet of Norwegian adults was estimated according to 24-h dietary recall data from a national dietary surveillance survey (Norkost 3). Scenario diets were modelled to represent the Norwegian FBDG and the EAT-Lancet healthy reference diet. Dietary environmental impact in terms of global warming potential, freshwater and marine eutrophication, terrestrial acidification, water use and transformation and use of land was estimated for the current and scenario diets using environmental impact data representative of the Norwegian market. Significant associations between impact and gender/educational attainment were assessed at P < 0·05.

SETTING

Norway.

PARTICIPANTS

Adults (n=1787) aged 18-70 years who participated in the Norkost 3 survey (2010-2011).

RESULTS

Environmental impact varied significantly by gender and educational attainment. The food groups contributing most to environmental impact of Norwegian diets were meat, dairy, beverages, grains and composite dishes. Compared with the current Norwegian diet, the FBDG scenario reduced impacts from 2 % (freshwater eutrophication) to 32 % (water use), while the EAT-Lancet scenario reduced impacts from 7 % (marine eutrophication) to 61 % (land use). The EAT-Lancet scenario resulted in 3-48 % larger reductions in impact than the FBDG scenario.

CONCLUSIONS

The Norwegian FBDG, while not as environmentally friendly as the EAT-Lancet reference diet, can still be an important tool in lessening environmental burden of Norwegian diets.

Environmental and nutritional assessment of young children's diets in Norway: comparing the current diet with national dietary guidelines and the EAT-Lancet reference diet

PURPOSE

Introducing healthy and sustainable diets early in life can promote lifelong healthy dietary patterns with a low environmental impact. Therefore, we aimed to estimate the environmental and nutritional consequences of a dietary change for 2-year-old children in Norway towards healthier dietary patterns.

METHODS

Environmental impacts of the current habitual diet among 2-year-olds (n = 1413) were estimated for six impact categories and compared with scenario diets based on the Norwegian food-based dietary guidelines (FBDG) and the EAT-Lancet Commission reference diet. Last, we evaluated the nutritional adequacy of the diets against the Norwegian nutrition recommendations for children aged 2-5 years. The current diet was assessed by an FFQ.

RESULTS

Environmental impacts of the current habitual diet were up to two times higher than those of the scenario diets. Compared with the current diet, impacts from the FBDG scenario diet were reduced by 35% for water use and 18% for terrestrial acidification, whereas impacts from the EAT-Lancet scenario diet were reduced by 51% for water use, 57% for terrestrial acidification, 36% for global warming potential and 27% for freshwater eutrophication. Milk and dairy products were the main contributors to environmental impacts in both the current diet and the FBDG scenario diet. The scenario diets were nutritionally adequate and improved the dietary quality among Norwegian 2-year-olds.

CONCLUSION

Compared to current diets among young children, more plant-based dietary patterns in line with national FBDG or the EAT-Lancet Commission reference diet can improve the nutritional adequacy of diets and simultaneously reduce environmental impacts.

Carbon Footprint of the Pork Product Chain and Recent Advancements in Mitigation Strategies

The carbon footprint of pork production is a pressing concern due to the industry's significant greenhouse gas emissions. It is crucial to achieve low-carbon development and carbon neutrality in pork production. Thus, this paper reviewed the recent studies about various sources of carbon emissions throughout the current pork production chain; feed production, processing, and manure management are the major sources of carbon emissions. The carbon footprint of the pork production chain varies from 0.6 to 6.75 kg CO2e·kg-1 pig live weight, and the carbon footprint of 1 kg of pork cuts is equivalent to 2.25 to 4.52 kg CO2e. A large reduction in carbon emissions could be achieved simultaneously if combining strategies of reducing transportation distances, optimizing farmland management, minimizing chemical fertilizer usage, promoting organic farming, increasing renewable energy adoption, and improving production efficiency. In summary, these mitigation strategies could effectively decrease carbon emissions by 6.5% to 50% in each sector. Therefore, a proper combination of mitigation strategies is essential to alleviate greenhouse gas emissions without sacrificing pork supply.

Exploring healthy and climate-friendly diets for Danish adults: an optimization study using quadratic programming

Background

A transition to healthy and sustainable diets has the potential to improve human and planetary health but diets need to meet requirements for nutritional adequacy, health, environmental targets, and be acceptable to consumers.

Objective

The objective of this study was to derive a nutritionally adequate and healthy diet that has the least deviation possible from the average observed diet of Danish adults while aiming for a greenhouse gas emission (GHGE) reduction of 31%, corresponding to the GHGE level of the Danish plant-rich diet, which lays the foundation for the current healthy and sustainable food-based dietary guidelines (FBDGs) in Denmark.

Methods

With an objective function minimizing the departure from the average observed diet of Danish adults, four diet optimizations were run using quadratic programming, with different combinations of diet constraints: (1) nutrients only (Nutri), (2) nutrients and health-based targets for food amounts (NutriHealth), (3) GHGE only (GHGE), and finally, (4) combined nutrient, health and GHGE constraints (NutriHealthGHGE).

Results

The GHGE of the four optimized diets were 3.93 kg CO₂-eq (Nutri), 3.77 kg CO₂-eq (NutriHealth) and 3.01 kg CO₂-eq (GHGE and NutriHealthGHGE), compared to 4.37 kg CO₂-eq in the observed diet. The proportion of energy from animal-based foods was 21%-25% in the optimized diets compared to 34% in the observed diet and 18% in the Danish plant-rich diet. Moreover, compared to the average Danish diet, the NutriHealthGHGE diet contained more grains and starches (44 E% vs. 28 E%), nuts (+230%), fatty fish (+89%), eggs (+47%); less cheese (-73%), animal-based fats (-76%), total meat (-42%); and very limited amounts of ruminant meat, soft drinks, and alcoholic beverages (all-90%), while the amounts of legumes and seeds were unchanged. On average, the mathematically optimized NutriHealthGHGE diet showed a smaller deviation from the average Danish diet compared to the Danish plant-rich diet (38% vs. 169%, respectively).

Conclusion

The final optimized diet presented in this study represents an alternative way of composing a nutritionally adequate and healthy diet that has the same estimated GHGE as a diet consistent with the climate-friendly FBDGs in Denmark. As this optimized diet may be more acceptable for some consumers, it might help to facilitate the transition toward more healthy and sustainable diets in the Danish population.

Current Practices and Opportunities for More Sustainable Public Food Procurement: A Qualitative Study among Danish Municipalities and Regions

Public food procurement has been emphasized as a powerful tool to promote a healthier and more sustainable food system, but there is still a long way to go to reach full potential. This study aimed to investigate practices and opportunities for sustainable and healthy public food procurement. A qualitative cross-sectional study was performed among Danish municipalities and regions stratified and randomly selected to cover standard practice (n = 17). In addition, interviews were performed among selected best-practice municipalities (n = 5) providing examples of ambitious goals and well-defined processes for obtaining sustainable food procurement. Large differences were observed in the cross-sectional analysis in relation to policy support and goals for sustainable food procurement, including organic purchase. Generally, there was a great attentiveness to reduce food waste and many valued the use of local food, especially among rural municipalities, whereas experience with climate impact reduction and shifts towards more plant-based menus was still in an early implementation stage. Results suggest a possible synergy effect between the use of organic food and efforts to reduce food waste and climate impact and emphasize the importance of local government policies to promote healthy and sustainable food procurement. Enabling factors to move sustainable food procurement forward are discussed.

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.