Abstract
BACKGROUND: The Mediterranean diet has been linked to beneficial physical and mental health outcomes, whereas sustainable food literacy supports environmentally responsible and health-conscious eating behaviors. Healthcare professionals, owing to their societal role, are a critical group for promoting these practices. OBJECTIVES: This study aimed to examine the relationships among Mediterranean diet adherence, sustainable food literacy, and depression levels among healthcare workers and to explore their associations with demographic and lifestyle factors. METHODS: A cross-sectional study was conducted with 251 healthcare workers. Data were collected via the Mediterranean Diet Adherence Screener (MEDAS), the Sustainable Food Literacy Scale, and the Beck Depression Inventory. Statistical analyses included correlation and regression models. RESULTS: Compared with men, women scored higher on the sustainable food literacy subdimension. Nonsmokers demonstrated greater adherence to the Mediterranean diet, whereas individuals with chronic diseases had higher depression scores. Individuals with chronic diseases reported higher depression levels. The lowest adherence rates within the MEDAS items were observed for wine, fish and seafood, and fruit consumption, whereas the highest adherence was found for using tomato–garlic–onion sauces and preferring white over red meat. The participants with minimal depression reported significantly higher MEDAS and food literacy (knowledge subscale) scores than did those with severe depression. MEDAS scores were positively correlated with sustainable food literacy and negatively correlated with body mass index. Regression analysis indicated that depression negatively predicted both the MEDAS score and the sustainable food literacy score. CONCLUSIONS: The findings emphasize the interconnectedness of adherence to the Mediterranean diet◊, sustainable food literacy, and mental health among healthcare professionals. Integrating nutrition education and promoting the Mediterranean diet may enhance psychological well-being while fostering sustainable eating behaviours. Future research should expand to diverse professional groups and evaluate the impact of targeted interventions. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12913-025-13675-9.