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

International audience; 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-Sante 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.