What is the primary effect of UV radiation on skin?

The primary effect of UV radiation on skin is to cause hyperpigmentation. When the skin is exposed to UV rays, it triggers a response from the melanocytes, which are the cells responsible for producing melanin, the pigment that gives skin its color. This process is a protective mechanism; the body produces more melanin to absorb and dissipate UV radiation, resulting in darker areas of skin, commonly known as sunspots or tans. Over time, excessive UV exposure can lead to uneven skin tone and contribute to conditions such as melasma and post-inflammatory hyperpigmentation.

The other options suggest effects that are not directly associated with UV radiation. For instance, while hydration is important for skin health, UV radiation tends to dehydrate the skin rather than boost its hydration. Elasticity is also affected over time, but UV exposure generally has a detrimental effect, leading to loss of collagen and elastin, rather than enhancing these properties. Similarly, UV radiation does not reduce oil production; in fact, it can sometimes stimulate oil production in certain skin types, affecting overall skin balance and health.