Food cravings are associated with increased self-regulation, even in the face of strong instigation habits: a longitudinal study of the transition to plant-based eating

Frequently engaging in a positive health behaviour, like following a vegetarian or vegan (veg*n) diet, can bring benefits to both the individual and society. We investigated the roles of two psychological determinants of behaviour—instigation habits and self-regulation strategy use—in a cohort of individuals who were newly transitioning to a veg*n diet. In a longitudinal study over 6 months (7 waves including baseline), 222 individuals transitioning to a veg*n diet reported their monthly habit strength, craving frequency, self-regulation strategies and animal product consumption. Our results supported the benefits of having a healthy habit, as stronger habits predicted fewer cravings and lower consumption of animal products, in line with the person's target diet. However, in contrast to some theoretical accounts, having a strong instigation habit did not reduce the use of self-regulation strategies; people with strong habits used multiple strategies to maintain their diet, especially when they experienced frequent diet-inconsistent cravings. These findings challenge the idea that habits eliminate the need for self-regulation, and suggest that habits do not fully circumvent motivational challenges in the pursuit of complex health behaviours. Our results are consistent with recent suggestions that automatic and intentional processes act simultaneously during the enactment of complex health behaviours.