The persistence of food preferences is a significant obstacle to changing unhealthy eating behavior. The current study investigates whether posthypnotic suggestions (PHSs), aiming to increase the desirability of healthy food items, can enhance food-related decisions. After assessing hypnotic susceptibility in Session 1, at the beginning of Session 2, PHS was delivered. After the termination of hypnosis, a set of two tasks was administrated twice, once when PHS was activated and once deactivated in counterbalanced order. The task set consisted of rating 170 pictures of food items, followed by an online supermarket where participants were instructed to select enough food for a fictitious week of quarantine. After one week, Session 3 mimicked Session 2 without renewed hypnosis induction to assess the persistence of the effects. The Bayesian hierarchical modeling indicates that PHS increased preferences and choices of healthy food items without altering the influence of preferences in choices. In contrast, for unhealthy food items, not only both preferences and choices were decreased due to PHS, but also their relationship was modified. Although choices became negatively biased against unhealthy items, preferences played a more dominant role in unhealthy choices when PHS was activated. Notably, all effects persisted over one week, qualitatively and quantitatively. Our results indicate that although PHS affected healthy choices through resolve, i.e., preferred more and chosen more, unhealthy items were probably chosen less impulsively through effortful suppression. Together, our results suggest PHSs as a promising tool for counteracting the overweight and obesity epidemic in modern societies.