How does UV radiation primarily affect the skin?

• A. By promoting melanin production
• B. By causing DNA damage and increasing cancer risk
• C. By thickening the skin layers
• D. By reducing moisture levels

Answer: (B)

UV radiation primarily affects the skin by causing DNA damage and increasing cancer risk. When skin cells are exposed to ultraviolet light, it can lead to mutations in the DNA. These mutations may disrupt the normal cell cycle and ultimately result in uncontrolled cell growth, which is a hallmark of cancer development. This mechanism underlines the increased incidence of skin cancers, such as melanoma, basal cell carcinoma, and squamous cell carcinoma, associated with excessive UV exposure.

While promoting melanin production, thickening skin layers, and reducing moisture levels are effects associated with UV exposure, they are not the primary concern when discussing the carcinogenic potential of UV radiation. Melanin production is a natural response to UV exposure that provides some level of protection against further damage, but it does not counteract the DNA damage that can occur. Similarly, thickening of skin layers may happen as a protective mechanism, and moisture loss can result from UV damage, but these outcomes do not encapsulate the most critical risk of skin cancer linked with UV radiation.