2.6. Covariates
eating habits
Covariates were determined based on their known or suspected association with the exposure and outcomes. Covariates were related to participants’ demographic information, lifestyle, socio-economic situation, and general health awareness, and were obtained from four main sources: (1) the study’s baseline questionnaire, (2) daily questions, (3) annual health check-up data, and (4) the wearable device. Demographic information included sex and age (continuous); lifestyle factors included eating habits with self-reported balanced food intake (yes/no), daily alcohol consumption (ethanol intake <20 g or ≥20 g as per the MHLW’s recommended daily limit [