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).
However, if it occurs frequently, you should have your eyes examined just in case it is a sign of something serious. Seeing stars is a common visual complaint, but it is usually a normal and harmless occurrence. If you close your eyes and rub them, you will probably see spots and flashes of light. These images you see are called phosphenes, an entoptic phenomenon characterized by the experience of seeing light without having light actually enter the eye. Phosphenes are produced by pressure on the eye.