How food literacy levels shape healthy eating intentions: a cross-sectional study of adults in Shandong Province, China, using the theory of planned behavior

Dietary choices play a crucial role in individual health, with food literacy being a key factor influencing these choices. Therefore, this study examined the relationship between food literacy and healthy eating intentions among adults in Shandong Province, China. Cross-sectional data were collected from 492 adults in Shandong Province, China, between October 2023 and January 2024, using a validated questionnaire that incorporated constructs from the theory of planned behavior (TPB) and food literacy (FL). The FL levels were categorized using the original 4-level classification, and multiple linear regression analyses were conducted, controlling for confounders to examine the associations across these levels. The scores for the behavioral intentions varied according to sociodemographic factors, such as education levels and physical activity. As the FL levels increased, the scores on all TPB constructs increased significantly, consistently, and linearly (all, P < 0.001, P for trend < 0.001). After adjusting for confounding variables, the perceived behavioral control remained a consistent and significant positive predictor of the behavioral intentions across all levels of FL (P < 0.001). Nevertheless, the subjective norms (P < 0.001) were positively associated with healthy eating intentions only among individuals in the lowest rank of FL, whereas the attitudes (P = 0.019) were positively associated with the behavioral intentions only among those in the highest rank. Individuals with lower FL levels were likelier to have their behavioral intentions influenced by others. In contrast, those with higher FL levels tended to hold more positive attitudes toward the benefits of healthy eating and showed greater willingness to seek detailed dietary information. These findings underscore the importance of developing targeted interventions to enhance FL and promote healthy eating intentions among adults in Shandong Province.