Objective: We aimed to explore the relationship between socio-economic characteristics and sustainable dietary patterns.
Design: Dietary data were derived from a web-based FFQ. Diet sustainability was evaluated using a modified Sustainable Diet Index, comprising nutritional, environmental and cultural components (higher scores expressing higher sustainability). The socio-economic position markers were education, household income and occupation status. Multi-adjusted linear and Poisson regression models were used to assess the cross-sectional association of the markers of socio-economic status with a sustainable diet and sustainability subcomponents, respectively.
Setting: France.
Participants: 29 119 NutriNet-Santé participants.
Results: Individuals with a more sustainable diet had slightly higher diet monetary cost, lower total energy intake and consumed less animal-based foods than their counterparts. Lower education level was associated with lower overall diet sustainability (βprimary v. postgraduate = -0·62, 95 % CI (-0·72, -0·51)) and nutrition, socio-cultural and environmental subscores. Manual workers and employees had a lower modified Sustainable Diet Index than intermediate professionals (βmanual workers v. intermediate professionals = -0·43, 95 % CI (-0·52, -0·33) and βemployees v. intermediate professionals = -0·56, 95 % CI (-0·64, -0·48)). Participants with the lowest v. highest incomes had a higher environmental subscore but a lower socio-cultural subscore, whereas the results were less marked for occupational status.
Conclusions: Overall, our results documented associations between socio-economic status and the level of diet sustainability, arguing for the implementation of appropriate food policies to promote sustainable diets at lower cost.
Keywords: Diet quality; Diet sustainability; Environmental sustainability; Observational study; Socio-economic status.