Alignment between greenhouse gas emissions reduction and adherence the EAT-Lancet diet: A modeling study based on the NutriNet-Santé cohort.

The potential of the EAT-Lancet reference diet, which promotes a healthy diet within planetary limits, to reduce greenhouse gas emissions (GHGe) remains understudied. This study examines the role of nutritional and acceptability constraints in reducing GHGe through diet optimization, and tests the alignment between GHGe reduction and the EAT-Lancet score. The study used data from 29,413 NutriNet-Santé participants to model French diets and evaluate their environmental, nutritional, economic, and health impact. The Organic Food Frequency Questionnaire was used to assess organic and conventional food consumed, and the Dialecte database was used to estimate the diet environmental impacts. Quality of diets were also evaluated based using the PNNS-GS2 (Programme National Nutrition-Santé 2 guidelines score). When testing minimizing GHGe under strict nutritional and acceptability constraints, it was possible to reduce GHGe up to 67 % (from 4.34 in the observed diet to GHGe = 1.45 kgeqCO2/d) while improving the EAT score by 103 % with 91 % of the food as organic. Greater reductions required relaxation of some constraints. When testing maximizing EAT score under gradual reduction in GHGe, the adherence to the EAT-Lancet diet was not significantly affected by the gradual reduction in GHGe. To maximize EAT score with 75 % reduction in GHGe (1.09 kgeqCO2/d), less strict constraints on the bioavailability of iron and zinc are necessary. The EAT score improved by 141 %, while land occupation decreased by 57 %, compared to the observed value. The diet contained 94 % of organic foods. There was some alignment between the degree of adherence to the EAT-Lancet diet and the reduction in GHGe, but other diets may also lead to a strong reduction in GHGe. Thus, GHGe can be greatly reduced by dietary choices, but require profound reshaping of diets which must be coupled with changes in other areas of the food chain.

Association between adherence to the EAT-Lancet diet and risk of cancer and cardiovascular outcomes in the prospective NutriNet-Santé cohort.

BACKGROUND: The EAT-Lancet commission proposed, in 2019, a planetary, healthy, and universal dietary pattern. However, this diet has rarely been studied in relation to various health outcomes. OBJECTIVES: We aimed to prospectively estimate the association between the EAT-Lancet diet and cancer and cardiovascular disease (CVD) risk. METHODS: The study was conducted in participants of the NutriNet-Santé cohort (2009-2021). The endpoints were the incident outcomes (cancer and CVDs and mortality from these diseases), combined and separately. Adherence to the EAT-Lancet diet was estimated using the EAT-Lancet Diet Index (ELD-I) modeled as quintiles (Qs). Multivariable Cox proportional hazard models were used to estimate HRs and 95% CIs, adjusted for potential confounders and moderators. RESULTS: A total of 62,382 subjects were included; 2475 cases of cancer and 786 cases of cardiovascular events occurred during a median follow-up of 8.1 y. The sample was 76% female, the mean ± SD age at inclusion was 51.0 ± 10.2 y. The ELD-I ranged from -162 to 332 points with a mean ± SD score of 45.4 ± 25.6 points. In multivariable models, no significant association between the EAT-Lancet diet and the risk of cancer and CVD combined, and separately, was observed. Alcohol consumption was an effect modifier of the association. A significant association was observed among low drinkers (HRQ5vs.Q1: 0.86; 95% CI: 0.73, 1.02; P-trend = 0.02). A higher ELD-I was significantly associated with a lower risk of overall cancer only among females (HRQ5vs.Q1: 0.89; 95% CI: 0.75, 1.05; P-trend = 0.03). Both associations were largely attenuated by BMI. CONCLUSIONS: Contrary to our hypothesis, our results documented significant associations between adherence to the EAT-Lancet diet and incidence of cancer only in some subgroups, and no association with CVD.This trial was registered at clinicaltrials.gov as NCT03335644.

Key Findings of the French BioNutriNet Project on Organic Food-Based Diets: Description, Determinants, and Relationships to Health and the Environment.

Few studies have investigated the relationships between organic food consumption, dietary patterns, monetary diet cost, health, and the environment. To address these issues, a consortium of French epidemiologists, nutritionists, economists, and toxicologists launched the BioNutriNet project in 2013. In 2014, an FFQ documented the usual organic and nonorganic (conventional) food consumption of approximately 35,000 NutriNet-Santé participants. Then, individual organic and conventional food intakes were merged with price, environmental, and pesticide residue data sets, which distinguished between conventional and organic farming methods. Many studies were conducted to characterize organic consumers and their environmental impacts (i.e., greenhouse gas emissions, energy demand, and land use) and organic food consumption impacts on health. We observed that organic consumers had diets that were healthier and richer in plant-based food than nonorganic consumers. Their diets were associated with higher monetary costs, lower environmental impacts, and reduced exposure to certain pesticide residues. Regular consumption of organic food was associated with reduced risks of obesity, type 2 diabetes, postmenopausal breast cancer, and lymphoma. Although several observations have been confirmed by several studies conducted in other countries, our results should be replicated in other cultural settings and coupled with experimental studies to be able to draw causal conclusions. Finally, the main finding of the BioNutriNet project is that while organic food consumption could be associated with positive externalities on human health and the environment, organic-based diets should be accompanied by dietary shifts toward plant-based diets to allow for better planetary and human health.

Halving food-related greenhouse gas emissions can be achieved by redistributing meat consumption: Progressive optimization results of the NutriNet-Santé cohort.

BACKGROUND: Diet-related greenhouse gas emissions (GHGe) mainly comes from animal-sourced foods. As progressive changes are more acceptable for a sustainable food transition, we aimed to identify nutritionally adequate and culturally acceptable optimized diets ensuring a gradual reduction in GHGe, using observed diet from a large sample of French adults, while considering the mode of food production (organic vs conventional farming) and the co-production link between milk and beef. MATERIAL AND METHOD: Based on the consumption of 257 organic and conventional foods among 29,413 participants (75% women, age: 53.5 ± 14.0y) of the NutriNet-Santé study, we modelled optimal diets according to GHGe reduction scenarios in 5% steps, from 0 to 50% with nutritional, acceptability, and coproduct constraints, for men, premenopausal and menopausal women separately. RESULTS: Gradual GHGe decrease under these constraints led to optimal diets with an overall decrease in animal foods, with marked reductions in dairy products (up to -83%), together with a stable but largely redistributed meat consumption in favor of poultry (up to +182%) and pork (up to +46%) and at the expense of ruminant meat (down to -92%). Amounts of legumes increases dramatically (up to +238%). The greater the reduction in diet-related GHGe, the lower the cumulative energy demand (about -25%) and land use (about -43%). The proportion of organic food increased from ~30% in the observed diets to ~70% in the optimized diets. CONCLUSION: Our results suggest that meeting both nutrient reference value and environmental objectives of up to 50% GHGe reduction requires the reduction of animal foods together with important substitutions between animal food groups, which result in drastic reductions in beef and dairy products. Further research is required to explore alignment with long-term health value and conflict with acceptability, in particular for even greater GHGe reductions.

Prospective associations between sustainable dietary pattern assessed with the Sustainable Diet Index (SDI) and risk of cancer and cardiovascular diseases in the French NutriNet-Santé cohort.

To ensure a sustainable development, it is essential to better characterize the relationships between diet sustainability and health. We investigated the associations between sustainable dietary patterns, assessed using the Sustainable Diet Index (SDI) and the risk of cancer and cardiovascular diseases in a large prospective cohort of French volunteers. We computed the SDI among 25,592 participants of the NutriNet-Santé cohort using a database developed within the BioNutriNet project comprising nutritional, behavioral, environmental and economic data. Health status of each participant was collected from 2014 to 2018 and validated by physicians. Associations between the SDI and risk of chronic diseases (cancer and cardiovascular diseases) were assessed using multivariable Cox models. 640 incident chronic diseases occurred during the 3.8-year follow-up (483 cancer cases and 158 cardiovascular disease cases). A higher SDI was associated with a lower risk of overall chronic diseases after adjustment for potential confounding factors. Participants in the fourth quartile, reflecting the highest sustainable dietary patterns, exhibited a significant decrease in risk of cancers or cardiovascular diseases (HRQ4 vs. Q1 = 0.61 (95% CI 0.47-0.80), P-trend = 0.0002). More specifically, this association was observed for cancers in the fully adjusted model but was not statistically significant for cardiovascular diseases. Although these results need to be confirmed by other observational studies, they support the fact that a wide adoption of sustainable dietary patterns may contribute to improving global health in France and argue for existing dietary patterns exhibiting cobenefits for human health and the environment.