What is the main cause of hyperpigmentation?

Hyperpigmentation primarily occurs due to increased melanin production in the skin, which often results from exposure to ultraviolet (UV) light. When the skin is exposed to UV rays, it triggers melanocytes (the cells responsible for producing melanin) to produce more of this pigment as a protective mechanism. This increase in melanin can lead to darker patches on the skin, commonly referred to as age spots or sunspots.

The role of UV exposure is significant, as it not only stimulates melanin production but can also damage skin cells and alter their function. Other factors such as hormonal changes, certain medications, or inflammatory skin conditions can also cause hyperpigmentation, but the mechanism remains centered around the increased production of melanin, particularly in response to UV light. Understanding this process is crucial for recognizing the effects of sun exposure on skin health and the importance of protective measures like sunscreen.