The role of health literacy in predicting adherence to nutritional recommendations: A systematic review

Objective: Synthesize quantitative empirical evidence on the role of health literacy in predicting adherence to dietary recommendations.

Methods: A systematic search of 13 online databases resulted in 1498 articles eligible for screening. Of those, 20 met the predefined inclusion criteria and, together with 6 studies retrieved from their reference lists, were included for review. Screening of full-texts, data extraction and quality appraisal were independently performed by two reviewers. Inconsistencies regarding eligibility were resolved through discussion.

Results: Of the 26 reviewed articles, 17 involved patients and 9 the general population. Overall, 35 associations between health literacy and various nutrition behaviours were observed. A significant direct positive association was reported in 5 cases, all of them concerning the general population. An insignificant association was reported in 20 cases, 15 of which were related to patients. The remaining associations were negative (n=2), partially mediated (n=1) or entirely mediated (n = 7).

Conclusion: Health literacy was scarcely determinant of dietary adherence and other nutrition behaviours, especially among patients.

Practice implication: Patients' dietary adherence is likely to be unaffected by interventions based on health literacy. Empowering approaches are expected to be more beneficial.