The widespread adoption of 24-hour continuous operations in a number of industries has resulted in an increase in the size of the population engaged in shift work. The health effects of shift work have been studied comprehensively. For ischemic heart disease, the reported relative risk of shift workers has ranged from 1.3 to 2.0. In terms of blood pressure, shift work has been clarified to be a significant risk factor for the onset of hypertension and increased blood pressure. Potential mechanisms of these health effects have been associated with disturbed circadian rhythms, sleep and lifestyle problems, increased stress and biochemical changes. Efficient health screening and support to control unhealthy lifestyle factors would be of considerable benefit for maintaining the health of shift workers.