The knowledge-behavior gap in nutritional literacy and its associations with chronic disease in older adults: a...

This study employs the Knowledge, Attitude, and Practice (KAP) model to examine the association between nutritional literacy and chronic disease occurrence among older adults in Guangxi, China, aiming to reveal the existence and mechanism of the "knowledge-behavior gap" in the adults' nutritional literacy.

From May to September 2025, a stratified random sampling method was utilized to conduct a questionnaire survey on nutritional literacy and chronic diseases among 9,249 urban and rural older adults from four cities in Guangxi. Factors influencing nutritional literacy were analyzed through multiple linear regression, and mediation effect testing using bootstrapping with 5,000 resamples.

This study revealed an average nutritional literacy score of 73.60 ± 9.80; besides, totally 4,024 participants (43.82%) suffered from chronic diseases. The total nutritional literacy and "behavior and skills" dimension scores were shown to be significantly higher in healthy older adults than those with chronic diseases (P < 0.05); however, their "knowledge and understanding" score was conversely low (P < 0.05), which indicated the knowledge-behavior gap. Regression analysis suggested that nutritional literacy knowledge and understanding enhanced both lifestyle/dietary behaviors and basic skills (P < 0.05), whereas both lifestyle and dietary behaviors and basic skills were negatively associated with chronic diseases (P < 0.05). The mediation effect analysis revealed the following masking effect: Although nutritional literacy knowledge had a positive direct effect on chronic diseases (β = 0.057, SE = 0.007, 95% CI = 0.044~0.071, P < 0.001), it exerted a negative total indirect effect on chronic diseases through behaviors and skills (β = -0.047, BootSE = 0.004, 95% Bootstrap CI = -0.056 ~ -0.039).

This study clarifies the existence of a knowledge-behavior gap in the nutritional literacy of older adults in Guangxi and the masking role played by nutritional knowledge and understanding in the relationship between nutritional literacy and chronic disease prevention/management. As a result, chronic disease prevention and management efforts should extend beyond the mere dissemination of theoretical knowledge to encompass intervention strategies centered on behavior promotion and skills training, aiming to realize their potential health benefits.