The article provides a comprehensive review of empirical studies on consumer attitudes, motivations, and behaviors in the functional food market. The main objective of this study is to identify groups of determinants and to update and systematize current knowledge on the influence of various factors on consumer purchasing decisions in this market. Based on an analysis of international research published between 2004 and 2025, four key groups of determinants were identified: (1) health- and trust-related factors, (2) cognitive and psychological factors, (3) perceptual and product-related factors, and (4) socio-demographic and segmentation factors. The analysis confirms that purchasing decisions in this product category are complex and multidimensional. They result from the interaction between rational factors (health-related and cognitive) and emotional-symbolic factors (psychological and sensory). The strongest predictors of functional food acceptance include perceived health benefits, trust in producers and information sources, sensory attractiveness, and product naturalness. Socio-demographic characteristics, such as age, education level, and income, further differentiate purchasing intentions and behaviors. Overall, the findings highlight the need for further comparative and cross-cultural research, as cultural and economic conditions may significantly shape consumer decisions across markets. The results obtained have both theoretical and practical implications. They contribute to a better understanding of consumer decision-making processes and emphasize the importance of promoting health awareness.