Healthcare shift workers are often linked to circadian misalignments, leading to irregular dietary behaviours, altered sleep patterns, and elevated health risks such as metabolic syndromes and psychological disorders. Despite growing recognition of these implications, limited studies have comprehensively explored how chrononutrition, sleep quality, and sleep patterns interrelate in this high-risk population. Hence, the current study aimed to examine these domains and their associations among rotating healthcare shift workers in Selangor, Malaysia. Using a cross-sectional design, all data were collected through a set of self-administered questionnaires, comprising sociodemographic data, the Malay version of the Chrononutrition Profile Questionnaire (CPQ-M), the Pittsburgh Sleep Quality Index (PSQI) and Munich Chronotype Questionnaire for Shift-Workers (MCTQ), to assess chrononutrition behaviours, sleep quality, sleep patterns and social jetlag. The findings highlighted widespread disruptions in both chrononutrition and sleep, with 40.8 % skipping breakfast, 66.0 % reporting poor sleep quality, and 53.4 % showing signs of social jet lag. A significant association (p < 0.05) was observed between sleep quality and night eating behaviour, indicating that poorer sleep quality was linked to increased likelihood of night eating among shift workers. However, the majority still maintained a consistent pattern of both an eating window of 10 to 13 h between the first and last meal of the day, as well as stable night eating behaviours, with no consumption of meals or snacks within two hours before bedtime. This study is among the few to comprehensively examine chrononutrition behaviours and sleep health among healthcare shift workers. The findings underscore the need for tailored interventions, such as promoting structured meal timings, enhancing access to healthy breakfasts in workplace cafeterias, and conducting educational workshops aimed at improving nutrition and sleep hygiene among participants. These measures can help to mitigate the adverse effects of shift work and support overall health and well-being. Shift
