By Suzanne Dixon, MPH, RD. Updated June 27, 2016. Learn how to prepare for colon cancer screening during the day before your scheduled examination. The day before a colonoscopy, you will begin having only clear liquids, starting with either lunch or dinner.
In addition, UV light stimulates melanin cells in skin, causing them to darken; when this happens, you have a tan. Unfortunately, there is no such thing as a safe tan. The UV light that burns or tans you damages skin cells in ways that can accelerate skin aging, and even increase your risk of developing skin cancer. There are two kinds of UV light: Ultraviolet A (UVA) and ultraviolet B (UVB).
So, now that we know all about the skin we can start to actually understand tans and sunburns. When you get a tan, what is actually happening is that the melanocytes are producing melanin pigment in reaction to ultraviolet light in sunlight. Ultraviolet light stimulates melanin production. The pigment has the effect of absorbing the UV radiation in sunlight, so it protects the cells from UV damage.