The relationship between sustainable dietary behaviors, sustainable food literacy, healthy life awareness, and social media addiction in adults: a cross-sectional study in Türkiye

BACKGROUND: Sustainable food literacy, healthy life awareness, and adherence to sustainable dietary models such as the Mediterranean diet are critical for promoting both public health and environmental well-being. While sociodemographic influences have been examined in previous research, the potential role of social media addiction as a behavioral factor in shaping sustainable dietary practices remains underexplored. OBJECTIVES: This study aimed to investigate how sustainable food literacy, healthy life awareness, and social media addiction relate to Mediterranean diet adherence and nutritional sustainability in adults, while also accounting for key sociodemographic characteristics. METHODS: This cross-sectional online study included 2,263 adults (60.5% female; mean age, 29.4 ± 11.7 years; mean BMI, 24.54 ± 6.8 kg/m²). Data were collected using the Sustainable Food Literacy Scale (SFLS), Social Media Addiction Scale (SMAS), Adherence to the Mediterranean Diet and Nutritional Sustainability Questionnaire Turkish Version (MedQ-Sus-Tr), and Healthy Life Awareness Scale (HLAS). Pearson correlation and multiple linear regression analyses were performed. RESULTS: Based on the MedQ-Sus-Tr, 91.0% of participants were classified as having low adherence to the Mediterranean diet, and 70.1% were classified as having low nutritional sustainability. Mediterranean diet adherence showed the strongest correlation with nutritional sustainability (r = 0.728, p < 0.001). Predictors of Mediterranean diet adherence included marital status, income, SFLS, and HLAS (R² = 0.365), while nutritional sustainability was predicted by marital status, income, SFLS, and HLAS (R² = 0.301). SFLS was associated with sex, education level, marital status, income, social media addiction, HLAS, Mediterranean diet adherence, and nutritional sustainability (R² = 0.704). HLAS was predicted by sex, age, SFLS, social media addiction, Mediterranean diet adherence, and nutritional sustainability (R² = 0.696). CONCLUSIONS: Our findings highlight that higher sustainable food literacy and healthy life awareness significantly predict greater adherence to the Mediterranean diet and improved nutritional sustainability, regardless of sociodemographic characteristics. Social media addiction was positively associated with both literacy and awareness, though it did not directly predict dietary adherence or sustainability. These results suggest that while social media use may enhance exposure to nutrition-related information, its impact on actual dietary behaviors is less direct. Targeted interventions should therefore leverage the informational potential of digital platforms, while also fostering translation of awareness into healthier and more sustainable eating practices.