Florent Vieux

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.

Individual diet modeling translates nutrient recommendations into realistic and individual-specific food choices

BACKGROUND Nutrient-based recommendations are defined for populations, but the dietary choices needed to fulfill them at the individual level deserve further exploration. OBJECTIVE The objective was to describe the dietary changes needed to achieve nutritional recommendations for each individual of a population. DESIGN An individual diet model was specifically developed for each adult participating in the French national INCA (Enquête Individuelle et Nationale sur les Consommations Alimentaires) dietary survey (n = 1171). Starting from each individual weekly food intake (observed diets), an isocaloric modeled diet was designed by linear programming to simultaneously meet the French nutrient recommendations for 32 nutrients while deviating the least from the observed food intake. Modeled diets were paired with observed diets for statistical comparison. RESULTS A new nutritionally adequate diet was obtained for each individual. In half the modeled diets, <5 of the foods usually consumed were replaced. The amount of foods selected in the modeled diets varied from individual to individual, and this variability followed that found in observed diets. Fruit, vegetables, grains, legumes, dried fruit, unsalted nuts, fresh dairy products, and fish were increased in modeled diets. Fatty fish and walnuts were added to each modeled diet. In contrast, red meats, deli meats, cheese, mixed dishes, and salted snacks were decreased. Sweets were also decreased but to a lesser extent. CONCLUSIONS This new individual diet modeling approach offers the possibility of translating nutrient recommendations into realistic food choices for all individuals from a representative population. The results showed that nutrient needs can be fulfilled in many different ways, depending on initial individual food patterns.

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.

The shortest way to reach nutritional goals is to adopt Mediterranean food choices: evidence from computer-generated personalized diets

BACKGROUND Dietary guidelines can be derived from dietary patterns known to be healthy such as the traditional Mediterranean diet. They can also be deduced by translating a set of nutrient recommendations into food combinations. However, the latter may vary depending on the decisions made by different expert committees. OBJECTIVE The objective was to compare the effect of removing or adding selected nutrient recommendations on the dietary changes needed to fulfill a whole set of nutrient recommendations. DESIGN For each adult participating in the French INCA dietary survey (Enquête Individuelle et Nationale sur les Consommations Alimentaires) (n = 1171), a nutritionally adequate diet was modeled that simultaneously met a whole set of nutrient goals (proteins, fiber, essential fatty acids, 10 vitamins, 9 minerals, sodium, saturated fatty acids, free sugars) while deviating the least from the observed diet in terms of food content. Eight sets of models were developed according to the inclusion or not of constraints on total fats, total carbohydrates, total MUFAs, and cholesterol. RESULTS Compared with the observed intakes, fulfilling the whole set of nutrient constraints systematically decreased total fats and increased total carbohydrates, even in the absence of specific constraints on those macronutrients. For whichever model used, a strong consistency was observed in the dietary changes needed to fulfill the constraints, and the greatest increases were seen for unsalted nuts, unrefined grains, legumes, fruit, fish and shellfish, and vegetables. CONCLUSION Whether recommendations on total fats, MUFAs, or total carbohydrates are included or not in the definition of overall nutrient adequacy, foods typical of the Mediterranean diet are needed to reach overall nutrient adequacy.

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.

To Meet Nutrient Recommendations, Most French Adults Need to Expand Their Habitual Food Repertoire

Simultaneous dietary achievement of a comprehensive set of nutrient recommendations is difficult. Our objective was to assess the feasibility of achieving a set of 30 nutrient recommendations at the individual level and characterize factors associated with feasibility. Seven-day food records collected from adults participating in the French national food consumption survey (n = 1171) were modified using an individualized diet optimization approach. For each individual, departure from his/her recorded diet was minimized, using only foods reported in his/her weekly diet record to fulfill a set of nutritional constraints. These constraints aimed to achieve or exceed the French Estimated Average Requirements and varied depending on the individuals gender, age, and observed nutrient intake levels. Acceptability constraints ensured realistic food portion sizes and food patterns. Model feasibility (i.e. percentage of feasible optimized diets) was calculated for all diets and by tertiles of dietary variety (i.e. the number of foods in the weekly food repertoire). Among the 1171 modeled diets, only 22% were mathematically feasible, showing that 78% of French adults would need to expand their weekly food repertoire to fulfill nutrient recommendations. Model feasibility increased from 6.6 to 50.3% and from 2.7 to 42.9% in tertiles 1 and 3 of dietary variety for men and women, respectively. The vitamin D constraint was the most difficult to fulfill (feasibility doubled after its removal), followed by sodium (maximum), magnesium (minimum), and SFA (maximum). The new approach developed in this study provides a method for identifying nutrient levels to carefully evaluate when establishing recommendations.

How low can dietary greenhouse gas emissions be reduced without impairing nutritional adequacy, affordability and acceptability of the diet? A modelling study to guide sustainable food choices.

OBJECTIVE To assess the compatibility between reduction of diet-related greenhouse gas emissions (GHGE) and nutritional adequacy, acceptability and affordability dimensions of diet sustainability. DESIGN Dietary intake, nutritional composition, GHGE and prices were combined for 402 foods selected among those most consumed by participants of the Individual National Study on Food Consumption. Linear programming was used to model diets with stepwise GHGE reductions, minimized departure from observed diet and three scenarios of nutritional constraints: none (FREE), on macronutrients (MACRO) and for all nutrient recommendations (ADEQ). Nutritional quality was assessed using the mean adequacy ratio (MAR) and solid energy density (SED). SETTING France. SUBJECTS Adults (n 1899). RESULTS In FREE and MACRO scenarios, imposing up to 30 % GHGE reduction did not affect the MAR, SED and food group pattern of the observed diet, but required substitutions within food groups; higher GHGE reductions decreased diet cost, but also nutritional quality, even with constraints on macronutrients. Imposing all nutritional recommendations (ADEQ) increased the fruits and vegetables quantity, reduced SED and slightly increased diet cost without additional modifications induced by the GHGE constraint up to 30 % reduction; higher GHGE reductions decreased diet cost but required non-trivial dietary shifts from the observed diet. Not all the nutritional recommendations could be met for GHGE reductions ≥70 %. CONCLUSIONS Moderate GHGE reductions (≤30 %) were compatible with nutritional adequacy and affordability without adding major food group shifts to those induced by nutritional recommendations. Higher GHGE reductions either impaired nutritional quality, even when macronutrient recommendations were imposed, or required non-trivial dietary shifts compromising acceptability to reach nutritional adequacy.

Individual diet modeling shows how to balance the diet of french adults with or without excessive free sugar Intakes

Dietary changes needed to achieve nutritional adequacy for 33 nutrients were determined for 1719 adults from a representative French national dietary survey. For each individual, an iso-energy nutritionally adequate diet was generated using diet modeling, staying as close as possible to the observed diet. The French food composition table was completed with free sugar (FS) content. Results were analyzed separately for individuals with FS intakes in their observed diets ≤10% or >10% of their energy intake (named below FS-ACCEPTABLE and FS-EXCESS, respectively). The FS-EXCESS group represented 41% of the total population (average energy intake of 14.2% from FS). Compared with FS-ACCEPTABLE individuals, FS-EXCESS individuals had diets of lower nutritional quality and consumed more energy (2192 vs. 2123 kcal/day), particularly during snacking occasions (258 vs. 131 kcal/day) (all p-values < 0.01). In order to meet nutritional targets, for both FS-ACCEPTABLE and FS-EXCESS individuals, the main dietary changes in optimized diets were significant increases in fresh fruits, starchy foods, water, hot beverages and plain yogurts; and significant decreases in mixed dishes/sandwiches, meat/eggs/fish and cheese. For FS-EXCESS individuals only, the optimization process significantly increased vegetables and significantly decreased sugar-sweetened beverages, sweet products and fruit juices. The diets of French adults with excessive intakes of FS are of lower nutritional quality, but can be optimized via specific dietary changes.

Assessing the construct validity of five nutrient profiling systems using diet modeling with linear programming

Nutrient profiling classifies individual food products according to their nutrient content. According to the WHO (World Health Organization), validation is a key step in the development of a nutrient profiling system. The aim was to assess the construct validity of five European nutrient profiling systems (Choices, Keyhole, (AFSSA), European Commission (EC) system and FoodProfiler). Construct validity was assessed for each of the five-selected nutrient profiling systems by testing whether healthy foods (that is, identified as eligible by the system) make healthy diets, and unhealthy foods (that is, non-eligible) make unhealthy diets, using diet modeling. The AFSSA, EC and FoodProfiler systems were identified as valid, but differences in their levels of permissiveness suggested some misclassified food products. The two other systems failed the construct validity assessment. Among these three systems, the EC system is the less demanding in terms of nutritional information, it would, therefore, be the easiest to implement for regulating nutrition and health claims in Europe.

The nutrient profile of traditional Lebanese composite dishes: comparison with composite dishes consumed in France

Primary objective: To estimate the overall nutritional quality of traditional Lebanese dishes by calculating their nutrient profile. Methods: Fifty traditional Lebanese composite dishes (LD) were compared with 50 composite dishes consumed in France (FD), based on the SAIN (score of nutritional adequacy of individual foods) and LIM (score of nutrients to be limited) nutrient profiling system. Each dish was attributed to one of four nutrient profiling classes based on their SAIN and LIM values. The dishes’ distributions within the four classes and their content in selected nutrients and ingredient groups were compared. Results: LD had a better nutrient profile than FD (P <0.001). LD were richer in vitamin C and contained less proteins, saturated fatty acids, and sodium. They contained more vegetables and unrefined starches and less cheese and refined starches than FD. Conclusions: Nutrient profiles may help identify those composite dishes whose consumption should be encouraged to promote healthy eating in Lebanon.