People with serious mental illness (SMI) are at risk of dying many years earlier than the general population. Providing an effective, cost-efficient healthcare service requires a holistic approach, and improving the physical health of people with SMI should be integral to all healthcare roles. It is important for nurses to identify and understand the barriers that people with SMI may experience when accessing physical healthcare. A range of factors contribute to reduced life expectancy, including lifestyle factors, symptoms of mental illness and the side effects of medications. This article discusses four areas of health that commonly affect people with SMI: metabolic syndrome, smoking, oral health and sexual health. Metabolic syndrome is a cluster of risk factors that increase an individual's risk of cardiovascular disease, stroke and type 2 diabetes mellitus. Smoking is increasingly prevalent in people with SMI, with rates remaining steady despite a decline in smoking rates nationally. Oral health and sexual health can negatively affect the physical health and well-being of people with SMI; however, these aspects of health are often neglected. This article identifies ways that nurses in all practice settings can use health promotion, assessment and treatment to improve the physical health of people with SMI in relation to these four areas.