Environmental pressures and pesticide exposure associated with an increase in the share of plant-based foods in the diet.

Diets rich in plant-based foods are encouraged for human health and to preserve resources and the environment but the nutritional quality and safety of such diets is debated. This study aimed to model nutritionally adequate diets with increasing plant food content and to characterise the derived diets using a multicriteria approach including, nutrients intake, environmental pressures and exposure to pesticides. Using data of the NutriNet-Santé cohort (N = 29,413), we implemented stepwise optimization models to identified maximum plant-food content under nutritional constraints. Environmental indicators at the production level were derived from the DIALECTE database, and exposure to pesticide residues from plant food consumption was estimated using a contamination database. Plant-based foods contributed to 64.3% (SD = 10.6%) of energy intake in observed diets and may reach up to 95% in modelled diets without jeopardizing nutritional status. Compared to the observed situation, an increase in plant-based foods in the diets led to increases in soy-based products (+ 480%), dried fruits (+ 370%), legumes (+ 317%), whole grains (+ 251%), oils (+ 144%) and vegetables (+ 93%). Animal products decreased progressively until total eviction, except for beef (- 98%). Dietary quality (estimated using the Diet Quality Index Based on the Probability of Adequate Nutrient Intake) was improved (up to 17%) as well as GHGe (up to - 65%), energy demand (up to - 48%), and land occupation (- 56%) for production. Exposures to pesticides from plant-based foods were increased by 100% conventional production and to a much lesser extent by 100% organic production. This study shows that shifting to nutritionally-adequate plant-based diets requires an in-depth rearrangement of food groups' consumption but allows a drastic reduction environmental impact. Increase exposure to pesticide residues and related risks can be mitigated by consuming foods produced with low pesticide input.

Sustainability analysis of the Mediterranean diet: results from the French NutriNet-Santé study.

The Mediterranean diet is often proposed as a sustainable diet model. This study aimed to evaluate the associations between adherence to the Mediterranean diet and sustainability domains in a cohort of French adults, using multiple criteria including nutritional quality, environmental pressures, monetary cost and dietary pesticide exposure. Food intakes of 29 210 NutriNet-Santé volunteers were assessed in 2014 using a semi-quantitative FFQ. Adherence to the Mediterranean diet was evaluated using the validated literature-based adherence score (MEDI-LITE). The associations between the MEDI-LITE and various sustainability indicators were examined using ANCOVA models, adjusted for sex, age and energy intake. Higher adherence to the MEDI-LITE was associated with higher nutritional quality scores, better overall nutrient profile as well as reduced environmental impact (land occupation: Q5 v. Q1: -35 %, greenhouse gas emissions: -40 % and cumulative energy demand: -17 %). In turn, monetary cost increased with increasing adherence to the Mediterranean diet (Q5 v. Q1: +15 %), while higher adherents to the Mediterranean diet had overall higher pesticide exposure due to their high plant-based food consumption. In this large cohort of French adults, greater adherence to the Mediterranean diet was associated with nutritional and environmental benefits, but also with higher monetary cost and greater exposure to pesticides, illustrating the necessity to develop large-scale strategies for healthy, safe (pesticide- and contaminant-free) and environmentally sustainable diets for all.

Associations between measures of socio-economic position and sustainable dietary patterns in the NutriNet-Santé study.

OBJECTIVE: We aimed to explore the relationship between socio-economic characteristics and sustainable dietary patterns. DESIGN: Dietary data were derived from a web-based FFQ. Diet sustainability was evaluated using a modified Sustainable Diet Index, comprising nutritional, environmental and cultural components (higher scores expressing higher sustainability). The socio-economic position markers were education, household income and occupation status. Multi-adjusted linear and Poisson regression models were used to assess the cross-sectional association of the markers of socio-economic status with a sustainable diet and sustainability subcomponents, respectively. SETTING: France. PARTICIPANTS: 29 119 NutriNet-Santé participants. RESULTS: Individuals with a more sustainable diet had slightly higher diet monetary cost, lower total energy intake and consumed less animal-based foods than their counterparts. Lower education level was associated with lower overall diet sustainability (ßprimary v. postgraduate = -0·62, 95 % CI (-0·72, -0·51)) and nutrition, socio-cultural and environmental subscores. Manual workers and employees had a lower modified Sustainable Diet Index than intermediate professionals (ßmanual workers v. intermediate professionals = -0·43, 95 % CI (-0·52, -0·33) and ßemployees v. intermediate professionals = -0·56, 95 % CI (-0·64, -0·48)). Participants with the lowest v. highest incomes had a higher environmental subscore but a lower socio-cultural subscore, whereas the results were less marked for occupational status. CONCLUSIONS: Overall, our results documented associations between socio-economic status and the level of diet sustainability, arguing for the implementation of appropriate food policies to promote sustainable diets at lower cost.

Nutritionally adequate and environmentally respectful diets are possible for different diet groups: an optimized study from the NutriNet-Santé cohort.

BACKGROUND: Research has shown that vegetarian diets have a low environmental impact, but few studies have examined the environmental impacts and nutritional adequacy of these diets together, even though vegetarian diets can lead to nutritional issues. OBJECTIVES: Our objective was to optimize and compare 6 types of diets with varying degrees of plant foods (lacto-, ovolacto-, and pescovegetarian diets and diets with low, medium, and high meat content) under nutritional constraints. METHODS: Consumption data in 30,000 participants were derived from the French NutriNet-Santé cohort using an FFQ. Diets were optimized by a nonlinear algorithm minimizing the diet deviation while meeting multiple constraints at both the individual and population levels: nonincrease of the cost and environmental impacts (as partial ReCiPe accounting for greenhouse gas emissions, cumulative energy demand, and land occupation, distinguishing production methods: organic and conventional), under epidemiologic, nutritional (based on nutrient reference values), and acceptability (according to the diet type) constraints. RESULTS: Optimized diets were successfully identified for each diet type, except that it was impossible to meet the EPA (20:5n-3) + DHA (22:6n-3) requirements in lacto- and ovolactovegetarians. In all cases, meat consumption was redistributed or reduced and the consumption of legumes (including soy-based products), whole grains, and vegetables were increased, whereas some food groups, such as potatoes, fruit juices, and alcoholic beverages, were entirely removed from the diets. The lower environmental impacts (as well as individual indicators) observed for vegetarians could be attained even when nutritional references were reached except for long-chain n-3 (omega-3) fatty acids. CONCLUSIONS: A low-meat diet could be considered as a target for the general population in the context of sustainable transitions, although all diets tested can be overall nutritionally adequate (except for n-3 fatty acids) when planned appropriately.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.

Conservative to disruptive diets for optimizing nutrition, environmental impacts and cost in French adults from the NutriNet-Santé cohort.

Improving the sustainability of diets requires the identification of diets that meet the nutritional requirements of populations, promote health, are within planetary boundaries, are affordable and are acceptable. Here we explore the extent to which dimensions of sustainability could be optimally aligned and identify more sustainable dietary solutions, from the most conservative to the most disruptive, among 12,166 participants of the NutriNet-Santé cohort. We aim to concomitantly lower environmental impacts (including greenhouse gas emissions, cumulative energy demand and land occupation), increase organic food consumption and study departure from observed diets (considered as a proxy for acceptability). From the most conservative to the most disruptive scenario, optimized diets were gradually richer in fruits, vegetables and soya-based products and markedly poorer in animal-based foods and fatty and sweet foods. The contribution of animal protein to total protein intake gradually decreased by 12% to 70% of the observed value. The greenhouse gas emissions from food production for the diets gradually decreased across scenarios (as a percentage of observed values) by 36-86%, land occupation for food production by 32-78% and energy demand by 28-72%. Our results offer a benchmark of scenarios of graded dietary changes against graded sustainability improvements.

Development and validation of an individual sustainable diet index in the NutriNet-Santé study cohort.

In the current context of unsustainable food systems, we aimed to develop and validate an index, the sustainable diet index (SDI), assessing the sustainability of dietary patterns, including multidimensional individual indicators of sustainability. Based on the FAO's definition of sustainable diets, the SDI includes seven indicators categorised into four standardised sub-indexes, respectively, environmental, nutritional, economic and sociocultural. The index (range: 4-20) was obtained by summing the sub-indexes. We computed the SDI for 29 388 participants in the NutriNet-Santé cohort study, estimated its validity and identified potential socio-demographic or lifestyle differences across the SDI quintile. In our sample, the SDI (mean=12·10/20; 95 % CI 12·07, 12·13) was highly correlated to all the sub-indexes that exerted substantial influence on the participants' ranking. The environmental and economical sub-indexes were the most and less correlated with the SDI (Pearson R 2 0·66 and 0·52, respectively). Dietary patterns of participants with a high SDI (considered as more sustainable) were concordant with the already published sustainable diets. Participants with high SDI scores were more often women (24 %), post-secondary graduates (22 %) and vegetarians or vegans (7 %), without obesity (16 %). Finally, the SDI could be a useful tool to easily assess the sustainability-related changes in dietary patterns, estimate the association with long-term health outcomes and help guide future public health policies.

Improvement of diet sustainability with increased level of organic food in the diet: findings from the BioNutriNet cohort.

BACKGROUND: Organic food consumption has steadily increased over the past decade in westernized countries. OBJECTIVE: The aim of this study, based on observational data, was to compare some sustainability features of diets from consumers with varying levels of organic food. METHODS: The diet sustainability among 29,210 participants of the NutriNet-Santé study was estimated using databases developed within the BioNutriNet project. Four dimensions (nutrition, environment, economy, and toxicology) of diet sustainability were assessed using: 1) nutritional indicators through dietary intakes and dietary scores, and BMI; 2) environmental indicators (greenhouse gas emissions, cumulative energy demand, and land occupation); 3) economic indicators via diet monetary costs; and 4) estimated daily food exposures to 15 pesticides. Adjusted means (95% CI) across weighted quintiles of organic food consumption in the diet were estimated via ANCOVA. Breakdown methods were used to disentangle the contribution of the production system (organic compared with conventional) from the dietary pattern in the variation of diet-related environmental impacts, monetary costs, and pesticide exposure, between the 2 extreme quintiles. RESULTS: Higher organic food consumption was associated with higher plant-food and lower animal-food consumption, overall nutritional quality (higher dietary scores), and lower BMI. Diet-related greenhouse-gas emissions, cumulative energy demand, and land occupation gradually decreased with increasing organic food consumption, whereas total diet monetary cost increased. Diet exposure to most pesticides decreased across quintiles. CONCLUSIONS: Diets of high organic food consumers were generally characterized by strong nutritional and environmental benefits. The latter were mostly driven by the low consumption of animal-based foods, whereas the production system was responsible for the higher diet monetary costs, and the overall reduced dietary pesticide exposure.

Corrigendum: Environmental Impacts of Plant-Based Diets: How Does Organic Food Consumption Contribute to Environmental Sustainability?

[This corrects the article on p. 8 in vol. 5, PMID: 29479530.].

Environmental Impacts of Plant-Based Diets: How Does Organic Food Consumption Contribute to Environmental Sustainability?

BACKGROUND: Studies investigating diet-related environmental impacts have rarely considered the production method of the foods consumed. The objective of the present study, based on the NutriNet-Santé cohort, was to investigate the relationship between a provegetarian score and diet-related environmental impacts. We also evaluated potential effect modifications on the association between a provegetarian score and the environmental impacts of organic food consumption. METHODS: Food intake and organic food consumption ratios were obtained from 34,442 French adults using a food frequency questionnaire, which included information on organic food consumption for each group. To characterize the overall structure of the diets, a provegetarian score was used to identify preferences for plant-based products as opposed to animal-based products. Moreover, three environmental indicators were used to assess diet-related environmental impacts: greenhouse gas (GHG) emissions, cumulative energy demand (CED), and land occupation. Environmental impacts were assessed using production life cycle assessment (LCA) at the farm level. Associations between provegetarian score quintiles, the level of organic food consumption, and environmental indicators were analyzed using ANCOVAs adjusted for energy, sex, and age. RESULTS: Participants with diets rich in plant-based foods (fifth quintile) were more likely to be older urban dwellers, to hold a higher degree in education, and to be characterized by an overall healthier lifestyle and diet. A higher provegetarian score was associated with lower environmental impacts (GHG emissionsQ5vsQ1 = 838/1,664 kg CO2eq/year, -49.6%, P < 0.0001; CEDQ5vsQ1 = 4,853/6,775 MJ/year, -26.9%, P < 0.0001; land occupationQ5vsQ1 = 2,420/4,138 m2/year, -41.5%, P < 0.0001). Organic food consumption was also an important modulator of the relationship between provegetarian dietary patterns and environmental impacts but only among participants with diets rich in plant-based products. CONCLUSION: Future field studies should endeavor to integrate all the components of a sustainable diet, i.e., both diet composition and production methods.