Are dietary changes over eight years in the prospective NutriNet-Sante cohort consistent with the EAT-Lancet reference diet?

Background: The transition toward sustainable dietary patterns, such as the planetary diet proposed by the EAT-Lancet Commission, is warranted to optimize health and achieve environmental sustainability. Objectives: To examine the extent to which the evolution of dietary changes over an 8-y period in the French NutriNet-Sante cohort aligned with the EAT-Lancet diet. Methods: A sample of 17,187 participants of the prospective NutriNet-Sante study was used. Dietary intakes were evaluated in 2014, 2018, and 2022 using a food frequency questionnaire. The alignment of dietary patterns with the EAT-Lancet diet was assessed using the EAT-Lancet dietary index (ELDI). Changes over time in the ELD-I score and component sub-scores were evaluated using linear mixed regression models. Results: The mean ELD-I score in 2014 (35.1 f 0.4 points) increased by a mean of 5.5 points [95% confidence interval (CI): 5.0, 5.9] in 2018, with no further increase in 2022 (+4.2 points compared with 2014: 95% CI: 3.6, 4.9). The increase in the ELD-I observed in 2018 was mostly explained by increases in the sub-scores of these components: Beef, lamb, and pork (+3.4 points; 95% CI: 3.1, 3.6, i.e., lower consumption), Fruits (+1.6 points; 95% CI: 1.3, 1.9, i.e., greater consumption), and Nuts (+1.1 points; 95% CI: 1.0, 1.2, i.e., greater consumption). Changes of similar magnitudes were observed between 2014 and 2022, except for the Fruits component, which showed a decrease (-1.3 points; 95% CI: -1.7, -0.9). Greater changes in the ELD-I score over time were observed for females, younger adults, and adults with high education levels. Conclusions: Results suggest that the slight shift toward more sustainable dietary patterns within the NutriNet-Sante cohort between 2014 and 2018 has stabilized in 2022. This suggests the need for strong efforts from various actors in the field of nutrition and public health that may facilitate the transition toward sustainable dietary patterns.