Purpose The development and commerce of functional foods (FF) is complex, expensive and risky. Besides technological obstacles and legislative aspects, consumer demands also need to be considered. The purpose of this study is to assess the Lebanese consumer’s knowledge, attitudes and acceptance of FF and functional ingredients. Design/methodology/approach A cross-sectional study recruited a convenience sample of adults living in Mount Lebanon in 2015. An interviewer-based questionnaire assessed socio-demographic factors, medical status, consumption and knowledge of FF and FI ingredients. The data were analyzed using statistical package for social sciences. Findings Out of 251 respondents, 40.6 and 32.0 per cent were knowledgeable about FF and FI, respectively, and 67.3 per cent consumed them. Calcium (48.0 per cent) and omega-3 (38.6 per cent) were identified as the most important FI. The consumption of FF was mainly owing to their nutritional benefits beyond basic nutrition (44.2 per cent); however, fearing artificial additives and their side effects (33.4 per cent) were reasons for rejecting them. FF knowledge was higher among young (p = 0.005) and single individuals (p = 0.002) and those going to the gym (p = 0.001), whereas willingness to learn about them was only associated with higher education (p < 0.001). Prebiotic yogurt consumption was higher among gym visitors (p = 0.017) and knowers of FF (p < 0.001). The consumption of protein bars and shakes was higher among males and those going to the gym (p < 0.001). The consumption of cereal bars was higher among young individuals, single, with high income, going to the gym and knowledgeable about FF (p < 0.05). Originality/value The findings are useful for market orientation, development and successfully negotiating new market opportunities of FF for both food industries and policymakers.