This study explores behavioral and demographic predictors of sustainability engagement in sustainable food choices among Romanian adults, addressing a regional gap in Eastern European sustainability research, based on an online non-probability sample of 406 respondents collected through an online cross-sectional survey, with voluntary response and snowball sampling techniques, conducted between 15 October 2024 and 30 January 2025. From 527 initial responses, 121 questionnaires were excluded due to incomplete or inconsistent answers, resulting in a final analytic sample of 406 respondents. A modified version of the Food Choice Questionnaire (FCQ), termed the Consumers’ Engagement in Food Choices Questionnaire (CEFCQ), was employed to capture sustainability-related behaviors and attitudes. Four hypotheses were tested using multiple linear regression. While snowball sampling is appropriate for exploratory research, we acknowledge its limitations in terms of representativeness at the national level. The respondents haven’t received any incentives, and data privacy and confidentiality were guaranteed. A modified version of the Food Choice Questionnaire (FCQ) was employed to assess sustainability-related attitudes and behaviors, including food label awareness, shopping frequency, and food waste reduction practices. Drawing on existing literature, four hypotheses were formulated and tested using multiple linear regression analysis. Results indicate that label reading behavior and perceived importance of digitalization are positively associated with sustainability engagement, while shopping frequency is negatively associated. Educational attainment and digital marketplace engagement show no significant association after controlling for other variables. The model explains approximately 25% of the variance in sustainability engagement. Given the non-probabilistic sampling design and demographic skew toward female and highly educated respondents, findings are interpreted as exploratory. This study contributes region-specific evidence on sustainable food behavior in Romania and highlights the role of information-oriented behaviors over formal education in predicting sustainability engagement. Implications for consumer education, labeling policy, and targeted interventions aligned with the European Green Deal are discussed.