Exposure to UV light is a main factor causing NMSC. UV light directly harms skin cells and also damages the skin’s immune system. Normally the skin’s immune system easily recovers, but for people with a compromised immune system this process might be too slow. In this case the risk for developing skin cancer increases.
People with a weak immune system, or those with a history of skin cancer, are at particular risk and should protect themselves from UV light. UV light may be delivered from natural or artificial sources. The sun emits different types of UV light, including ultraviolet A (UVA; long-wave) and ultraviolet B (UVB; short-wave) rays. Both UVA and UVB reach the earth and play an important role in premature skin aging, eye damage (including cataracts) and certain skin cancers. It is important to know that 90% of the UV light penetrates through clouds so that people at risk need to protect themselves every day, whatever the weather.
Protecting your skin from UV exposure
Protection from UV exposure can mean prevention of skin cancer. So it is important to keep in mind that, particularly for people with an increased risk for skin cancer, strict UV avoidance is necessary throughout the year. UV exposure should be avoided during all seasons of the year (from spring to winter) and even on cloudy days.