The goal of this observational cohort study is to delineate the five-year dynamic trajectories of metabolic phenotypes in Chinese adults with overweight or obesity, with or without type 2 diabetes, focusing on transition rates from metabolically healthy overweight/obesity to unhealthy overweight/obesity or to type 2 diabetes, as well as the incidence and progression of diabetic complications and cardiovascular events in those with type 2 diabetes and overweight/obesity. Researchers will compare three phenotype groups, namely metabolically healthy overweight/obesity, metabolically unhealthy overweight/obesity, and type 2 diabetes with overweight/obesity, to assess differences in metabolic parameter changes, complication rates, and cardiovascular risk. Participants will use a digital health management platform for data upload and lifestyle support, and will complete comprehensive health assessments at baseline, at 2.5 years, and at 5 years, along with annual light follow-ups.