The Nurse Cohort Study Xiamen (NCSX) is an open-ended prospective cohort study with very broad research aims. The primary objectives of the NCSX is planned to examine genetic, epigenetic, biological, psychological, social, lifestyle and other environmental factors of nurses in relation to incidence and progression of the common chronic diseases, such as hypertension, ischemic heart disease, stroke, diabetes, chronic kidney disease and some cancers, which are emerging with economic development in Xiamen, China. Specifically, we intend to test whether empirically driven hypothesis and emerging risk factors mainly developed in response to observations in economically developed Western societies apply in a population living in a rapid changing lifestyle in China now.