Young Adults’ Perceptions of Sustainable Diets: A Comparison Across Five High- and Middle-Income Countries

Sustainable diet transitions are required to protect human and planetary health, and consumers are important food systems actors who can foster positive changes. However, little is known about how consumers perceive the concept of sustainable diets. This study explored perceptions of sustainable diets across five high- and middle-income countries: Japan, Indonesia, Italy, Canada, and Mexico. Semi-structured interviews were conducted with 184 young adults (30–45 per country), and transcripts were analyzed using values coding to understand the values, attitudes, and beliefs that shape behaviours related to sustainable diets. Results revealed that defining “sustainable eating” was challenging for participants across all countries. While participants’ values regarding sustainable diets were often context-specific with marked differences across countries, common themes across countries included concern about food waste and packaging and the belief that sustainability should be the responsibility of all actors across the food system, not just the individual. These findings indicate that food policy should address both individual and systemic dimensions of food sustainability, specifically prioritizing strategies for waste and packaging infrastructure. Furthermore, public health strategies must be values-oriented and culturally tailored to ensure they resonate with local consumer priorities.