ABSTRACT
BACKGROUND: High automaticity in healthy nutrition behaviors is related to long-term maintenance of these behaviors. Drawing upon theoretical frameworks of habit formation, proposed antecedents such as intrinsic reward, anticipated regret, and self-efficacy are important correlates of automaticity, but not much is known about their day-by-day relationships with automaticity in healthy nutrition behaviors. This study tested previous-day within-person (i.e., from one day to the next) and same-day within-person associations of intrinsic reward, anticipated regret, and self-efficacy with automaticity of a healthy nutrition behavior, for which participants attempted to form a new habit. METHODS: Secondary analyses of a randomized controlled trial with two planning intervention conditions including a longitudinal sample of n = 135 participants (age: M = 24.82 years; SD = 7.27) are reported. Participants formed a plan on a self-selected healthy nutrition behavior to become a new habit and were followed up over 12 weeks assessing daily levels of plan-specific intrinsic reward, anticipated regret, self-efficacy, and automaticity. Lagged multilevel models with 84 study days nested in participants estimated previous-day within-person, same-day within-person, and between-person relationships of intrinsic reward, anticipated regret, and self-efficacy with automaticity. FINDINGS: Regarding within-level relationships, higher-than-usual levels of intrinsic reward, anticipated regret, and self-efficacy of the same day but not of the previous day were associated with higher within-person automaticity. With respect to between-level relationships, higher between-levels (i.e., higher person mean levels across the study period) of intrinsic reward, anticipated regret, and self-efficacy were linked with higher automaticity. DISCUSSION: Findings point towards the potential to intervene on intrinsic reward, anticipated regret, and self-efficacy when aiming to promote a new healthy nutrition habit.
ABSTRACT
OBJECTIVES: Habit formation has been identified as one of the key determinants of behaviour change. To initiate habit formation, self-regulation interventions can support individuals to form a cue-behaviour plan and to repeatedly enact the plan in the same context. This randomized controlled trial aimed to model habit formation of an everyday nutrition behaviour and examined whether habit formation and plan enactment differ when individuals plan to enact their behaviour in response to a routine-based versus time-based cue. DESIGN: Following a baseline assessment, N = 192 adults (aged 18-77 years) were randomly assigned to a routine-based cue or a time-based cue planning intervention, in which they selected an everyday nutrition behaviour and linked it to a daily routine or a time cue. METHODS: Participants responded to daily questionnaires over 84 days assessing plan enactment and the behaviour's automaticity (as an indicator of habit formation). Multilevel models with days nested in participants were fitted. RESULTS: As indicated by asymptotic curves, it took a median of 59 days for participants who successfully formed habits to reach peak automaticity. Group-level analyses revealed that both routine-based and time-based cue planning led to increases in automaticity and plan enactment, but no between-condition differences were found. Repeated plan enactment was a key predictor for automaticity. CONCLUSIONS: Linking one's nutrition behaviour to a daily routine or a specific time was similarly effective for habit formation. Interventions should encourage persons to repeatedly carry out their planned behaviour in response to the planned cue to facilitate habit formation.