The growing consumer interest in functional foods and healthy eating can unfortunately lead to the spread of misinformation and the belief in food-related myths. This study analyzed Brazilian consumers’ perceptions and beliefs about facts and myths regarding functional foods, focusing on attitudes, reference groups, and sociocultural factors affecting their perception. A theoretical model was developed, incorporating constructs such as attitudes (reward, trust, necessity, safety), beliefs, and reference groups. Data from 600 participants in the Southeast (n = 300) and Northeast (n = 300) of Brazil were collected through online questionnaires, with responses measured on a five-point Likert scale. Myths (widely held ideas lacking scientific basis) and ‘facts’ (evidence-based information) regarding functional food were selected via literature review and validated by nutrition experts. Structural equation modeling revealed that perceived necessity and reward were positively associated with myths, while safety perception was negatively associated with myths. Reference groups and beliefs were positively associated with facts. Cluster analysis identified two consumer profiles: (1) safety-conscious individuals, who prioritize food safety, and (2) engaged critics, influenced by reference groups and actively seeking information. These findings highlight the importance of culturally tailored communication strategies for countering myths and promoting functional foods in Brazil. Regulatory bodies in Brazil must enhance oversight of health claims to build consumer trust and encourage informed choices, fostering mindful consumption habits.