Health psychology is the study of psychological and behavioural processes in health, illness, and healthcare (Johnston, 1994). It is concerned with understanding how psychological, behavioral, and cultural factors contribute to physical health and illness.

Health Psychology is also concerned with the application of psychological theory, research, and practice to the promotion and maintenance of health, the identification and improvement of psychological factors contributing to physical illness/injury and supporting people to make health behaviour changes in line with their chosen values.