Edinburgh Napier University

  Many people are motivated to eat healthily but find it difficult to override established and less healthy habits. Habits by their nature are unconscious and cued by the environment, thus making them powerful determinants of behaviour. Limited research has explored the role of habit as a mediator between self-regulation and sugar consumption. This study investigated the relative importance of factors that support/impede the consumption of foods with high sugar content and the mediating effect of habit. The study sample was 500 Irish adult’s representative of the population. Sugar consumption, habit, hedonic hunger, self-efficacy, perceived need, dietary planning and dietary self-monitoring were assessed using self-reported measures. A path analysis of the data was used to test the direct and indirect effects of the independent factors on estimated sugar consumption grams per day (g/d). In addition, the interaction effects of self-efficacy and dietary planning/self-monitoring on sugar consumption was examined using simple slope analysis. The results showed that habit had the largest effect in the model and was positively related to sugar consumption g/d (b = 12.09, p < 0.01). While the direct effect of self-efficacy on sugar-consumption g/d was significant (b = −5.25, p < 0.05), this effect was partially mediated by habit (−4.84, Bca CI −7.00, −3.00) and the direct effect of action control on sugar consumption (b = −1.30, p = 0.311) was fully mediated by habit (b = −2.42, Bca CI −3.93, −1.20), which indicates that strong unhealthy habits compete against self-efficacy and can reduce the potential benefits of dietary planning and self-monitoring. The simple slope analysis revealed that action control has a significant negative effect on sugar intake when self-efficacy is weak (b = −5.48, p = 0.01). The direct effect of hedonic hunger on confectionery sugar consumption (b = 1.38, p = 0.376) was fully mediated by habit (b = 5.92, Bca CI 4.20, 8.08) indicating that the desire to eat tempting food may overrides one’s intended behaviour resulting in counter-intentional habits. It is apparent from the findings that a dual strategy of targeting behaviour and the underlying habits may be effective in improving dietary intake and self-regulation is likely to be sustainable only in an environment that facilitates healthy eating behaviour.