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.

The nature of protein intake as a discriminating factor of diet sustainability: a multi-criteria approach.

Animal production is responsible for 56-58% of the GHG emissions and limiting meat consumption would strongly contribute to reducing human health risks in Western countries. This study aimed to investigate the nature of protein intake as a discriminating factor for diets' sustainability. Using data from 29,210 French adults involved in the NutriNet-Santé cohort, we identified clusters according to 23 protein sources. A multicriteria (environmental, economic, nutritional and health) sustainability analysis was then conducted on the identified clusters. The economic analysis focused on both food and protein expenditure structures, using a budget coefficient approach. Relative values of clusters compared to the whole sample were calculated. We identified five clusters: milk-based, meat-based, fast food-based, healthy-fish-based, and healthy-plant-based. We found that the healthy-plant-based and healthy-fish-based clusters were the most sustainable, conciliating the compromise between human health (0.25 and 0.53 respectively for the Health Risk Score) and the protection of the environment (- 62% and - 19% respectively for the pReCiPe indicator). Conversely, the highest environmental impacts (+ 33% for the pReCiPe indicator) and the highest health risk (0.95 for the HRS) were observed for the meat-based cluster, which was associated with the lowest nutritional scores (- 61% for the PNNS-GS2 score). The economic analysis showed that the healthy-plant-based cluster was the one with the highest food budget coefficient (+ 46%), followed by the healthy-fish-based cluster (+ 8%), partly explained by a strong share of organic food in the diet. However, the meat-based cluster spent more of their food budget on their protein intake (+ 13%), while the healthy-plant-based cluster exhibited the lowest expenditure for this intake (- 41%). Our results demonstrate that the nature of protein intake is a discriminating factor in diet sustainability. Also, reducing animal protein consumption would generate co-benefits beyond environmental impacts, by being favorable for health, while reducing the monetary cost associated with protein intake.

Stages of Change toward Meat Reduction: Associations with Motives and Longitudinal Dietary Data on Animal-Based and Plant-Based Food Intakes in French Adults.

BACKGROUND: Reducing meat consumption is advocated for healthier and more sustainable diets. However, behavioral studies are needed to better understand the mechanisms underlying meat-reducing dietary changes. OBJECTIVES: The main aim of this study was to compare the motives associated with stages of change toward meat reduction in French adults, using the transtheoretical model (TTM). A second aim was to investigate the associations between stages of change and adherence to dietary patterns favoring a better balance of animal and plant food consumption over time. METHODS: This longitudinal study included 25,143 non-vegetarian participants of the web-based NutriNet-Santé cohort with a mean follow-up of 6.2 (SD = 2.6) y. Dietary data were obtained from 24-h dietary records over the period 2009-2019. The contribution of meat to total energy intake and scores measuring the contribution of healthy and unhealthy plant-based foods to the diet were computed. A questionnaire completed in 2018 allowed us to identify the TTM stages of change related to meat reduction (precontemplation, contemplation, preparation, action, and maintenance), and recorded motives related to meat consumption. We used multivariate linear mixed models for repeated data to assess associations between food intake changes and stages, and logistic regression for motives, presented as adjusted frequencies. RESULTS: Participants in later stages were characterized by a significantly higher decrease in meat intake over time, compared with the earliest stage (for example, ßmaintenance ∗ time = -0.08, P < 0.0001), and a higher increase in the healthy plant-based food consumption score over time (for example, ßmaintenance∗time = 0.11, P < 0.0001). Concerns about health, nutrition, and the environment were the most frequently cited motives for reducing meat consumption at all stages. CONCLUSIONS: Individuals who had already initiated meat reduction adhered to healthier and more sustainable diets than meat continuers. Characterizing motives according to readiness to reduce meat consumption could support tailored public health campaigns. TRIAL REGISTRATION NUMBER: The study protocol is registered at clinicaltrials.gov with Clinical Trial Registry number NCT03335644 available at https://clinicaltrials.gov/ct2/show/NCT03335644.

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.

Higher adherence to the EAT-Lancet reference diet is associated with higher nutrient adequacy in the NutriNet-Santé cohort: a cross-sectional study.

BACKGROUND: In 2019, the EAT-Lancet Commission proposed a planetary and healthy reference diet; however, its nutritional quality has been rarely evaluated. OBJECTIVE: Across different adherence levels to the EAT-Lancet reference diet, the following were our objectives:1) describe the food and nutritional intakes of the French population, 2) evaluate the nutrient quality, and 3) investigate the consistency between the French national recommendations and the EAT-Lancet reference diet. METHODS: This cross-sectional study was conducted among participants of the NutriNet-Santé cohort, and the sample was weighted on the characteristics of the general French population. Adherence to the EAT-Lancet reference diet was estimated using the EAT-Lancet Diet Index (ELD-I). Usual nutrient intakes were obtained using the variance reduction method. We used the estimated average requirements cut-point method to estimate the proportion of participants who meet their respective nutritional requirements. Furthermore, the adequacy of the French food-based dietary recommendations [Programme National Nutrition Santé (PNNS)] according to adherence to the EAT-Lancet reference diet was studied. RESULTS: The weighted sample was composed of 98,465 participants. Except for bioavailable zinc and vitamin B12, we observed a decrease in the nutrient inadequacy prevalence when the adherence to the EAT-Lancet reference diet increased, particularly for vitamin B9 (Q1 = 37.8% compared with Q5 = 5.5%, P < 0.0001) and vitamin C (Q1 = 59.0% compared with Q5 = 10.8 %, P < 0.0001). However, inadequacy prevalence remained high in all ELD-I quintiles, particularly for fiber (95.9%), vitamin B1 (70.8%), iodine (48.4%), and magnesium (76.8%). Higher ELD-I score was associated with higher adherence for most components of the PNNS, except for food groups that are not specifically included in the EAT-Lancet reference diet and are typical of the French diet, including alcohol, processed meat, and salt. CONCLUSION: In the French context, although issues with the intake of certain nutrients may occur, a diet that remains within the planetary limits as the EAT-Lancet reference diet allows a favorable nutritional quality. This trial was registered at clinicaltrials.gov as NCT03335644.

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.

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.

Are recent dietary changes observed in the NutriNet-Santé participants healthier and more sustainable?

PURPOSE: While intensive modern food systems have significant unfavourable impacts on health and the environment, new sustainable food consumption trends have been emerging in recent years. This study identified recent dietary trends over a 4-year period in terms of overall dietary patterns and organic foods consumption and associated socio-demographic determinants. METHODS: Food intakes were assessed among 18,108 participants of the NutriNet-Santé cohort in 2014 and 2018. A food frequency questionnaire was used to estimate organic and conventional food consumption. Change in food consumption, quality of the diet (assessed by the adherence to the French national guidelines), plant-based diet using published scores, organic food intake were evaluated in regard with various socio-demographic factors. The paired student t test to compare dietary intake and the Kruskal-Walllis test to consider socio-demographic characteristics were used. RESULTS: Consumption of meat and processed meat decreased respectively by 5.09 g/day (SD 51.15) and 1.12 g/day (SD 26.05). The average total consumption of organic products increased by 12% (+ 93 g/day) while consumption of organic fish and seafood (- 1.4 g/day), poultry (- 1 g/day), processed meat (- 0.3 g/day) and meat (- 3.3 g/day) decreased. The dietary towards healthier diets was more pronounced in certain population subgroups. For example, females, young individuals and postgraduate participants were more likely to increase their consumption of healthful plant and animal-based foods, organic foods and to improve the overall nutritional quality of their diets during the follow-up period than their counterparts. CONCLUSION: Our results indicate a slight inflexion towards healthier and plant-based diets over a 4-year period at least in some segments of the population. A decrease in the consumption of animal products and an increase in the consumption of healthful plant-based foods and organic foods suggests a potential trend towards more sustainable diets among certain subgroups. The environmental impacts of these changes need to be assessed in further works as well as the way to sustain and improve them, in particular those who do not initiate sustainable transition.

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.