Chronodisruption as an Emerging Determinant of Weight Loss Trajectories after Metabolic Bariatric Surgery: A Scoping Review.

Chronodisruption, i.e. the misalignment between endogenous circadian rhythms and behavioral or environmental cues, is an underrecognized determinant of weight outcomes following metabolic bariatric surgery (MBS). This scoping review synthesizes evidence from 18 primary human studies examining associations of chronodisruption with post-bariatric weight outcomes across six domains: sleep quality and timing, chronotype, social jetlag, chrononutrition, shift work, and seasonality. There is preliminary evidence that late bedtime, poor sleep quality, evening chronotype, high social jetlag, late meal timing, and shift work are each associated with suboptimal clinical response or accelerated recurrent weight gain, though most included studies did not adjust for key confounders including surgical type, caloric intake, and depression. Surgery does not appear to correct the underlying circadian misalignment. Light at night remains entirely unexamined in post-MBS populations despite robust population-level evidence linking it to obesity risk. Prospective evaluation of chronobiological profiling as a component of multidisciplinary bariatric evaluation is warranted, but current evidence remains insufficient to support its routine clinical adoption.