One in every three cancers diagnosed is a skin cancer. The main factor that predisposes to the development of skin cancer is exposure to ultraviolet (UV) radiation, traditionally from the sun and more recently from artificial tanning sunbeds. Both solar radiation and sunbeds are classified as carcinogenic to humans by the WHO International Agency for Research on Cancer (IARC).

Small amounts of UV are essential for the production of vitamin D in people, yet overexposure may result in acute and chronic health effects on the skin, eye and immune system.