Dietary Pattern Trajectories in French Adults of the NutriNet-Santé Cohort Over Time (2014-2022): Role of Socioeconomic Factors.

While dietary transitions towards more plant-based diets are urgently needed, few studies have investigated current diet trajectories, based on observed longitudinal data. This study investigated current dietary transitions of French adults over an 8 years period (2014-2022), while assessing the diet quality and the role of diverse socio-economic factors.Consumption data from 17,187 NutriNet-Santé cohort participants weighted for the French Census were collected using a food frequency questionnaire in 2014, 2018, and 2022. Adopting a gender-specific approach, consumption changes in 23 food groups were assessed over time. The diet quality was evaluated using the Comprehensive Diet Quality Index (cDQI) score, categorizing foods into "healthy" and "unhealthy". The socioeconomic analysis targeted four food groups (red meat (including fresh beef, pork, offal, and lamb), processed meat (e.g. sausages, ham, and bacon), legumes, and wholegrain products), strongly linked to mortality risk and recognized as significant markers of the sustainable diet transition. All analyses were conducted using multi-adjusted mixed-effects models.Consumption of some healthy plant-based foods (nuts +59 %, legumes +22%, wholegrain products +7%) significantly increased over time; while consumption of some unhealthy foods (red meat -19%, refined cereals -18%, sweetened drinks -15%) decreased. Conversely, consumption of prepared and mixed dishes (+16%), and processed meat (+35%) increased. These changes differed in magnitude between genders and translated into an improved diet quality score (cDQI). Occupational status was linked to longitudinal changes in food consumption, showing increased consumption of plant-based foods among students and higher socio-professional categories.Our findings provide accurate data on trends and factors for targeted initiatives, guiding strategic interventions for a sustainable dietary transition.