Effective policies to promote sugar reduction in soft drinks: lessons from a comparison of six European countries.

BACKGROUND: Many countries have sought to incentivise soft drinks manufacturers to reduce sugar in their products as part of efforts to address a growing prevalence of obesity. Are their policies effective? METHODS: Using a difference-in-differences design, we compared trends in the sugar content of 10 695 new sugar-sweetened beverages (SSB) launched between 2010 and 2019 in six European markets, including the UK and France (taxes designed to incentivise reformulation), the Netherlands (policy based on voluntary agreements to reduce sugar), Germany, Italy and Spain (no national policies). RESULTS: The announcement in 2016 and adoption in 2018 of the UK tax led to yearly reductions in average sugar content of 17% (95% CI: 15-19%) to 31% (13-48%) between 2016 and 2019, compared to 2015, while the 2018 French tax produced a 6% (95% CI: 5-7%) sugar reduction only in 2018, compared to 2017, shortly after it was redesigned to provide a stronger incentive for reformulation. Voluntary agreements implemented in the Netherlands in 2014 led to an 8% (95% CI: 4-13%) sugar reduction only in 2015, compared to 2013. CONCLUSION: The analysis supports the conclusions that sugar reductions in new SSBs have been greater in countries that have adopted specific policies to encourage them; a sugar-based tax design encourages more sugar reductions than a volume-based tax design; the tax rate and the amount of the tax reduction from switching to the next lower tier in a sugar-based tax design may be critical to incentivize reformulation.

Shifts in dietary patterns and risk of type-2 diabetes in a Caribbean adult population: ways to address diabetes burden.

PURPOSE: As the French West Indies are facing an ongoing nutrition transition with increasing type-2 diabetes mellitus (T2DM) prevalence, our study aimed to evaluate the effect of potential shifts in dietary patterns on T2DM risk in French West Indian adults according to several scenarios. METHODS: We used a cross-sectional multistage sampling survey on dietary intake conducted in 2013 on a representative sample of Guadeloupeans and Martinicans adults (n = 1063). From previously identified current dietary patterns, we used PRIME-Diabetes, a comparative risk assessment model, to estimate the effect of potential shifts from the "transitioning" pattern to the "convenient," the "prudent," and the "traditional" ones on T2DM risks. RESULTS: Potential shift in dietary intakes from the "transitioning" pattern to the "traditional" one reduced the T2DM risk in women (- 16% [- 22; - 10]) and in men - 14% [- 21; - 7]), as the shift in dietary intakes toward the "prudent" pattern (- 23% [- 29; - 17] and - 19% - 23; - 14], respectively). These risk reductions were mostly driven by increased whole grains, fruits, green leafy vegetable intakes, and decreases in potatoes, red meats, processed meats, and sugar-sweetened beverages. The shift in dietary intakes toward the "convenient" pattern did not affect the T2DM risks. CONCLUSION: To curb the increase in T2DM prevalence and reduce this burden, one public health action could be to target transitioning adults and help them to shift towards a diet associated with a reduced risk of T2DM as a prudent or a traditional diet.

Life cycle inventory and assessment data for quantifying the environmental impacts of a wide range of food products belonging to the same food category: A case study of 80 pizzas representatives of the French retail market.

Most of the time, Life Cycle Assessments (LCA) of food products are performed only on one representative of a food category. This doesn't allow us to understand the possible variations of environmental impacts within a food product category and the responsible factors for these variations. For this reason, LCAs were conducted for 80 different industrial pizzas representative of the French retail market. The LCAs were performed using the "EF 3.0 Method (adapted) V1.00/EF 3.0 normalization and weighting set" on SimaPro software. Most of the data used were taken from the AGRIBALYSE 3.0 and Ecoinvent 3.6 databases. The system perimeter goes from the production of the ingredients to the pizza consumption. The functional unit used was 1 kg of ready-to-eat pizza. Life cycle inventories were made to include the different flows in the LCA (materials, transport, energy, water, waste, etc.). The dataset contains details on products, life-cycle inventories (LCI) and LCIA results. These data can enrich the discussion on the need to study the environmental impacts of different products belonging to the same food category and not only one representative in order to avoid erroneous conclusions.

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.

Impact of intra-category food substitutions on the risk of type 2 diabetes: a modelling study on the pizza category.

Advice on replacing unhealthy foods with healthier alternatives within the same food category may be more acceptable and might ease the transition towards a healthy diet. Here, we studied the potential impact of substitutions within the pizza category on the risk of type 2 diabetes (T2D). The study sample consisted of 2510 adults from the INCA2 French national survey. Based on their nutritional characteristics, the 353 pizzas marketed in France were grouped into 100 clusters that were used to run various scenarios of pizza substitutions, which were either isoenergetic (IE) or non-isoenergetic (NIE). We then used a model structurally similar to the Preventable Risk Integrated ModEl to assess the expected rate of change in risk of T2D. Pizzas characterised by a low energy, high vegetable content and whole grain dough were associated with a greater reduction in the risk of T2D. The rates of change in risk of T2D were markedly stronger in men and for NIE substitutions. When the rates of change were estimated in the subsample of pizza consumers, replacing the observed pizzas with the best pizza resulted in a T2D risk reduction of -6·7 % (-8·4 %; -4·9 %, IE) and -8·9 % (-11·2 %; -6·3 %, NIE), assuming that this is their usual diets. The greatest risk reduction induced by an IE substitution of the observed pizza with a mixed dish was similar to that observed with the best pizzas. Overall, this modelling study suggests that healthy swaps within a category can effectively supplement broader dietary changes towards a healthier diet.

Demographic and socio-economic shifts partly explain the Martinican nutrition transition: an analysis of 10-year health and dietary changes (2003-2013) using decomposition models.

OBJECTIVE: The Caribbean has seen a dramatic shift in the obesity and chronic disease prevalence over the past decades, suggesting a nutrition transition. Simultaneously, Martinique has faced a demographic transition marked by significant population ageing. We aimed to differentiate the contribution of changes in health status and dietary intakes due to shifts in demographic and socio-economic characteristics (DSEC) from that due to unobserved factors. DESIGN: Two cross-sectional surveys conducted in 2003 (n 743) and 2013 (n 573) on representative samples were used. Dietary intakes were estimated by 24-h recalls. The contribution of changes in health status and dietary intakes due to shifts in observed DSEC was differentiated from that due to unobserved factors over a 10-year interval, using Oaxaca-Blinder decomposition models. SETTING: Martinique, French region in the Caribbean. PARTICIPANTS: Martinican adults (≥16 years). RESULTS: Over the study period, health status deteriorated, partly owing to shifts in DSEC, explaining 62 % of the change in the prevalence of hypertension (+13 percentage points (pp)) and 48 % of waist circumference change (+3 cm). Diet quality decreased (mean adequacy ratio -2pp and mean excess ratio + 2 pp) and energy supplied by ultra-processed food increased (+4 pp). Shifts in DSEC marginally explained some changes in dietary intakes (e.g. increased diet quality), while the changes that remained unexplained were of opposite sign, with decreased diet quality, lower fruits, tubers and fish intakes and higher energy provided by ultra-processed foods. CONCLUSION: Explained dietary changes were of opposite sign to nutrition transition conceptual framework, probably because unobserved drivers are in play, such as food price trends or supermarkets spread.

Public health potential of guidelines-based dietary scores for non-communicable diseases mortality prevention: simulation study using the Preventable Risk Integrated ModEl (PRIME) model.

OBJECTIVE: Dietary indexes measure the adherence of individuals to a set of nutritional recommendations. However, the health gains associated with adherence to various dietary indexes may vary. Our objective was to compare the magnitude of estimated avoided deaths by chronic diseases obtained by improving diet quality in the French population, measured by a variety of dietary indexes. DESIGN: Simulation study based on observational data. SETTING: Weighted data from a French population-based cohort study. PARTICIPANTS: In participants from the NutriNet-Santé cohort, we computed dietary scores reflecting the adherence to various recommendations (Medi-Lite, Healthy Diet Indicator (HDI), Programme National Nutrition Santé/National Nutrition and Health Program - Guidelines Score, Diet Quality Index (DQI), Alternative Healthy Eating Index (AHEI) and the modified Food Standards Agency nutrient profiling system dietary index (FSAm-NPS DI)). Quintiles of the food groups' consumption and dietary intakes were used as input in a simulation model (Preventable Risk Integrated ModEl (PRIME)), yielding the number of delayed or avoided deaths in nutrition-related non-communicable diseases, comparing between very high or very low nutritional quality of the diet and medium nutritional quality. RESULTS: A modification of dietary intakes from medium quality to very low quality (i.e. from the middle quintile to the quintile with the lowest nutritional quality) was associated with an increased number of deaths ranging from 3485 (95 % uncertainty interval (CI) 4002, 2987) for HDI and 3379 (95 % CI 3881, 2894) for FSAm-NPS DI to 838 (95 % CI 1163, 523) for Medi-Lite. Conversely, a modification of dietary intakes from medium quality to very high quality was associated with a decrease in the number of deaths ranging from 1995 (95 % CI 1676, 2299) for Probability of Adequate Nutrient intake diet, 1986 (95 % CI 1565, 2361) for DQI-International, 1931 (95 % CI 1499, 2316) for FSAm-NPS DI and 858 (95 % CI 499, 1205) for HDI. CONCLUSIONS: Our results provide some insights as the potential impact of following various dietary guidelines to reduce mortality from nutrition-related diseases.

Annotation data about multi criteria assessment methods used in the agri-food research: The french national institute for agricultural research (INRA) experience.

This data article contains annotation data characterizing Multi Criteria Assessment (MCA) Methods proposed in the agri-food sector by researchers from INRA, Europe's largest agricultural research institute (INRA, http://institut.inra.fr/en). MCA can be used to assess and compare agricultural and food systems, and support multi-actor decision making and design of innovative systems for crop production, animal production and processing of agricultural products. These data are stored in a public repository managed by INRA (https://data.inra.fr/; https://doi.org/10.15454/WB51LL).

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.

Accounting for consumers' preferences in the analysis of dietary recommendations.

BACKGROUND/OBJECTIVES: The goal of this article is to present and demonstrate the applicability of an original method to assess the economic and health impacts of compliance with food-based recommendations. The method takes account of consumers' preferences and the associated adoption cost in the assessment of various recommendations. SUBJECTS/METHODS: We combine an economic model of diet choice with an epidemiological model to compute the health impacts of dietary changes. To demonstrate the use of the method, we analyse the impacts of a 5% variation in the consumption of seven food groups taken separately: a 5% increase in consumption of fruits and vegetables (F&V) and milk products; and a 5% decrease in consumption of red meat, all meats, salty/sweet products, ready meals and butter/cream/cheese. RESULTS: A recommendation, when adopted by consumers, generates important changes in the whole diet due to substitutions and complementarities among foods. All simulated recommendations have a positive impact on health. The F&V recommendation has the largest impact on the number of DALYs averted, but the highest adoption cost for consumers, especially for low-income consumers. Alone, the change in energy intake explains from 71% to 98% of the DALYs averted induced by a recommendation. CONCLUSIONS: Small increases in recommended foods have the potential of generating relatively significant health gains. Preference-driven substitutions among foods have a major effect on simulated health outcomes and should be included in the assessment of dietary recommendations, together with the adoption cost borne by consumers.

Food reformulation and nutritional quality of food consumption: an analysis based on households panel data in France.

BACKGROUND/OBJECTIVES: We aimed to quantify the contribution of food reformulation to changes in the nutritional quality of consumers' food purchases, and compare it with the impact of substitutions made by consumers. SUBJECTS/METHODS: Using a brand-specific data set in France, we considered the changes in the nutrient content of food products in four food sectors over a 3-year period. These data were matched with data on consumers' purchases to estimate the change in the nutritional quality of consumers' purchases. This change was divided into three components: the reformulation of food products, the launching of new products and the consumers' substitutions between products. Key nutrients were selected for each food group: breakfast cereals (sugar, fats, SFA, fiber, and sodium), biscuits and cakes (sugar, fats, SFA, and fiber), potato chips (fats, SFA, and sodium) and soft drinks (sugar). RESULTS: Product reformulation initiatives have improved existing products for most food group-nutrient pairs. In particular, the contribution of food reformulation to the change in nutritional quality of food purchases was strong in potato chips (the sales-weighted mean SFA and sodium contents decreased by 31.4% to 52.1% and 6.7% to 11.1%, respectively), and breakfast cereals (the sales-weighted mean sodium content decreased by 7.3% to 9.7%). Regarding the launching of new products, the results were ambiguous. Consumers' substitutions between food items were not generally associated to an improvement in the nutritional quality of the food purchases. CONCLUSIONS: Policies aiming to promote food reformulation may have greater impact than those promoting changes in consumer behavior.

Assessment of the Sustainability of the Mediterranean Diet Combined with Organic Food Consumption: An Individual Behaviour Approach.

Mediterranean diets are promising sustainable food models and the organic food system may provide health and environmental benefits. Combining the two models could therefore be a favourable approach for food sustainability. The aim of this study was to draw up a comparative description of four diets differing in the level of organic foods consumption and the adherence to the Mediterranean diet, using multidisciplinary indicators to assess the sustainability of these diets. Four groups of participants were defined and compared, combining the proportion of organic food in their diet (Org versus Conv) and the adherence to the Mediterranean diet (Med versus NoMed). Conv-NoMed: Conventional consumers and non-Mediterranean diet followers; Conv-Med: Conventional consumers and Mediterranean diet followers; Org-NoMed: Organic consumers and non-Mediterranean diet followers; Org-Med: Organic consumers and Mediterranean diet followers. The adherence to nutritional recommendations was higher among the Org-Med and Conv-Med groups compared to the Conv-NoMed group (using the mPNNS-GS (modified-Programme National nutrition santé guidelines score/13.5 points): 9.29 (95% confidence intervals (CI) = 9.23-9.36) and 9.30 (95% CI = 9.24-9.35) versus 8.19 (95% CI = 8.17-8.22)) respectively. The mean plant/animal protein intake ratio was 1.38 (95% CI = 1.01-1.74) for the Org-Med group versus 0.44 (95% CI = 0.28-0.60) for the Conv-NoMed group. The average cost of the diet of Org-Med participants was the highest: 11.43 €/day (95% CI = 11.34-11.52). This study highlighted the importance of promoting the Mediterranean diet combined with organic food consumption for individual health and environmental aspects but challenges with regard to the cost remain.

Improving diet sustainability through evolution of food choices: review of epidemiological studies on the environmental impact of diets.

The Food and Agriculture Organization defines sustainable diets as nutritionally adequate, safe, healthy, culturally acceptable, economically affordable diets that have little environmental impact. This review summarizes the studies assessing, at the individual level, both the environmental impact and the nutritional quality or healthiness of self-selected diets. Reductions in meat consumption and energy intake were identified as primary factors for reducing diet-related greenhouse gas emissions. The choice of foods to replace meat, however, was crucial, with some isocaloric substitutions possibly increasing total diet greenhouse gas emissions. Moreover, nutritional adequacy was rarely or only partially assessed, thereby compromising the assessment of diet sustainability. Furthermore, high nutritional quality was not necessarily associated with affordability or lower environmental impact. Hence, when identifying sustainable diets, each dimension needs to be assessed by relevant indicators. Finally, some nonvegetarian self-selected diets consumed by a substantial fraction of the population showed good compatibility with the nutritional, environmental, affordability, and acceptability dimensions. Altogether, the reviewed studies revealed the scarcity of standardized nationally representative data for food prices and environmental indicators and suggest that diet sustainability might be increased without drastic dietary changes.

Quality standards versus nutritional taxes: Health and welfare impacts with strategic firms.

The goal of this paper is to better understand firms' strategic reactions to nutritional policies targeting food quality improvements and to derive optimal policies. We propose a model of product differentiation, taking into account the taste and health characteristics of products. We study how two firms react to alternative policies: an MQS policy, linear taxation of the two goods on the market, and taxation of the low-quality good. The MQS and the taxation of the low-quality product are the preferred options by a social planner. If taste is moderately important, the MQS policy is chosen by a populist and a paternalist social planner. If taste is a major component of choice, the populist planner chooses to tax the low-quality product whereas the paternalist planner prefers the MQS policy. Finally, for a paternalist social planner, an MQS-based policy always allows for higher levels of welfare than an information policy alone.

Beyond Wishful Thinking: Integrating Consumer Preferences in the Assessment of Dietary Recommendations.

Convenience, taste, and prices are the main determinants of food choices. Complying with dietary recommendations therefore imposes a "taste cost" on consumers, potentially hindering adoption of those recommendations. The study presents and applies a new methodology, based on economic theory, to quantify this taste cost and assess the health and welfare effects of different dietary recommendations. Then, by comparison of those effects, we identify socially desirable recommendations that are most compatible with consumer preferences (i.e., that best balance health benefits against"taste cost") and should be prioritized for promotion. The methodology proceeds in three-steps: first, an economic-behavioral model simulates how whole diets would change if consumers complied with dietary recommendations; second, an epidemiological model estimates the number of deaths avoided (DA) due to the dietary change; third, an efficiency analysis weighs the health benefits against the taste and policy costs of each recommendation. The empirical model is calibrated using French data. We find that recommendations to reduce consumption of red meat and soft-drinks, or raise consumption of milk products and fish/seafood impose relatively moderate taste costs. By comparison, recommendations related to F&V consumption and, to a lesser extent, butter/cream/cheese, snacks, and all meats impose larger taste costs on consumers. The F&V recommendation is the costliest for consumers to comply with, but it also reduces diet-related mortality the most, so that a large budget could be allocated to promoting F&V consumption while keeping this policy cost-beneficial. We conclude that promotion of most dietary recommendations improves social welfare. Our framework complements the programming models available in nutrition and public health: those models are best used to identify dietary targets, following which our framework identifies cost-beneficial ways of moving towards those targets.

Economic assessment of nutritional recommendations.

The effect of consumers' compliance with nutritional recommendations is uncertain because of potentially complex substitutions. To lift this uncertainty, we adapt a model of consumer behaviour under rationing to the case of linear nutritional constraints. Dietary adjustments are derived from information on consumer preferences, consumption levels, and nutritional contents of foods. A calibration exercise simulates, for different income groups, how the French diet would respond to various nutrition recommendations, and those behavioural adjustments are translated into health outcomes through the DIETRON epidemiological model. This allows for the ex-ante comparison of the efficiency, equity and health effects of ten nutritional recommendations. Although most recommendations impose significant taste costs on consumers, they are highly cost-effective, with the recommendations targeting salt, saturated fat, and fruits and vegetables (F&V) ranking highest in terms of efficiency. Most recommendations are also economically progressive, with the exception of that targeting F&V.

Identifying sustainable foods: the relationship between environmental impact, nutritional quality, and prices of foods representative of the French diet.

BACKGROUND: Sustainable diets, as defined by the Food and Agriculture Organization, need to combine environment, nutrition, and affordability dimensions. However, it is unknown whether these dimensions are compatible, and no guidance is available in the official recommendations. OBJECTIVE: To identify foods with compatible sustainability dimensions. METHODS: For 363 of the most commonly consumed foods in the Second French Individual and National Study on Food Consumption, environmental impact indicators (ie, greenhouse gas [GHG] emissions, acidification, and eutrophication), and prices were collected. The nutritional quality of the foods was assessed by calculating the score for the nutritional adequacy of individual foods (SAIN) to score for disqualifying nutrients (LIM) ratio. A sustainability score based on the median GHG emissions, price, and SAIN:LIM was calculated for each food; the foods with the best values for all three variables received the highest score. RESULTS: The environmental indicators were strongly and positively correlated. Meat, fish, and eggs and dairy products had the strongest influence on the environment; starchy foods, legumes, and fruits and vegetables had the least influence. GHG emissions were inversely correlated with SAIN:LIM (r=-0.37) and positively correlated with price per kilogram (r=0.59); the correlation with price per kilocalorie was null. This showed that foods with a heavy environmental impact tend to have lower nutritional quality and a higher price per kilogram but not a lower price per kilocalorie. Using price per kilogram, 94 foods had a maximum sustainability score, including most plant-based foods and excluding all foods with animal ingredients except milk, yogurt, and soups. Using price per kilocalorie restricted the list to 42 foods, including 52% of all starchy foods and legumes but only 11% of fruits and vegetables (mainly 100% fruit juices). CONCLUSIONS: Overall, the sustainability dimensions seemed to be compatible when considering price per kilogram of food. However, this conclusion is too simplistic when considering price per kilocalorie, which highlights the need to integrate the data at the diet level.

Reducing energy intake and energy density for a sustainable diet: a study based on self-selected diets in French adults.

BACKGROUND: Studies on theoretical diets are not sufficient to implement sustainable diets in practice because of unknown cultural acceptability. In contrast, self-selected diets can be considered culturally acceptable. OBJECTIVE: The objective was to identify the most sustainable diets consumed by people in everyday life. DESIGN: The diet-related greenhouse gas emissions (GHGE) for self-selected diets of 1918 adults participating in the cross-sectional French national dietary survey Individual and National Survey on Food Consumption (INCA2) were estimated. "Lower-Carbon," "Higher-Quality," and "More Sustainable" diets were defined as having GHGE lower than the overall median value, a probability of adequate nutrition intake (PANDiet) score (a measure of the overall nutritional adequacy of a diet) higher than the overall median value, and a combination of both criteria, respectively. Diet cost, as a proxy for affordability, and energy density were also assessed. RESULTS: More Sustainable diets were consumed by 23% of men and 20% of women, and their GHGE values were 19% and 17% lower than the population average (mean) value, respectively. In comparison with the average value, Lower-Carbon diets achieved a 20% GHGE reduction and lower cost, but they were not sustainable because they had a lower PANDiet score. Higher-Quality diets were not sustainable because of their above-average GHGE and cost. More Sustainable diets had an above-average PANDiet score and a below-average energy density, cost, GHGE, and energy content; the energy share of plant-based products was increased by 20% and 15% compared with the average for men and women, respectively. CONCLUSIONS: A strength of this study was that most of the dimensions for "sustainable diets" were considered, ie, not only nutritional quality and GHGE but also affordability and cultural acceptability. A reduction in diet-related GHGE by 20% while maintaining high nutritional quality seems realistic. This goal could be achieved at no extra cost by reducing energy intake and energy density and increasing the share of plant-based products.

High nutritional quality is not associated with low greenhouse gas emissions in self-selected diets of French adults.

BACKGROUND: Healthy diets are supposed to be more environmentally friendly because they rely mainly on plant-based foods, which have lower greenhouse gas emissions (GHGEs) per unit weight than do animal-based foods. OBJECTIVES: The objectives were to estimate the GHGEs associated with the consumption of self-selected diets in France and to analyze their relation with the nutritional quality of diets. DESIGN: For each adult in the national dietary Individual and National Survey on Food Consumption (n = 1918), the GHGEs of his or her diet were estimated based on the GHGEs of 391 foods. Highest-nutritional-quality diets were defined as those having simultaneously 1) an energy density below the median, 2) a mean adequacy ratio (MAR) above the median, and 3) a mean excess ratio (MER, percentage of maximum recommended values for nutrients for which intake should be limited) below the median. RESULTS: MAR was positively correlated and MER was negatively correlated with diet-related GHGEs. High-nutritional-quality diets contained more plant-based foods, notably fruit and vegetables, and fewer sweets and salted snacks than did low-quality diets. After adjustment for age, sex, and energy intake, the consumption of sweets and salted snacks was negatively correlated with diet-related GHGEs, whereas the consumption of animal products and of fruit and vegetables was positively associated with them. After adjustment for energy intake, high-nutritional-quality diets had significantly higher GHGEs (+9% and +22% for men and women, respectively) than did low-nutritional-quality diets. CONCLUSION: Despite containing large amounts of plant-based foods, self-selected diets of the highest nutritional quality are currently not those with the lowest diet-related GHGEs.