Recent lifestyle change impacts sleep and circadian rhythms among the Indigenous peoples of Peninsular Malaysia.

Sleep disorders are rising globally, but their lifestyle causes remain unclear. We recorded sleep-wake patterns via actigraphy from 1039 Orang Asli adults in Peninsular Malaysia experiencing varying levels of market integration, including access to permanent electrical and housing infrastructure, use of digital technologies, and participation in wage labour. We evaluated associations between these lifestyle variables and sleep timing, continuity and quantity, while accounting for relevant demographic and environmental covariates. Access to powerline electricity was associated with delayed and less regular sleep timing, shorter sleep duration and fewer nighttime disruptions. Ambient temperature more strongly influenced sleep onset than offset, resulting in shorter sleep under hotter conditions. Housing structure modestly shaped sleep timing: individuals living in wood or concrete housing woke earlier and showed reduced sensitivity of sleep timing to ambient temperature, indicating that built environments can modify thermal influences on sleep. Participation in wage labour was associated with fewer nighttime awakenings but not with shifts in sleep timing. Age and sex were strong predictors of sleep variation, with older adults sleeping earlier, with more regularity, and with fewer disruptions. These findings show that market integration exerts heterogeneous, context-dependent effects across multiple sleep outcomes.