Socioeconomic Status and the Prediction of Health Promoting Dietary Behaviours: A Systematic Review and Meta-Analysis Based on the Theory of Planned Behaviour

Background Dietary behaviours are strongly patterned by socioeconomic status (SES). However, the role of SES in the self-regulation of health promoting dietary behaviours is not fully understood. This systematic review with meta-analysis investigated whether four individual-level measures of SES (income, occupation, education, and ethnicity) moderate the relationships between Theory of Planned Behaviour (TPB) variables and different health promoting dietary behaviours in adults. Methods A systematic literature search identified 106 studies from 77 articles providing information on TPB variables, SES, and health promoting dietary behaviours-choosing health promoting foods and restricting health compromising foods. Random-effects meta-analyses were conducted to generate pooled correlations corrected for sampling and measurement error, and meta-regression was used to test moderating effects of study-level SES. Results All TPB variables were significantly and positively associated with both health promoting dietary behaviours, with intention having the strongest correlation with behaviour. However, none of the relationships between TPB variables and health promoting dietary behaviours were significantly moderated by study-level SES. Conclusions Results suggest robust associations between TPB predictors and healthy dietary behaviour that are not patterned by individual-level SES measures.