Photoaging: Current Concepts on Molecular Mechanisms, Prevention, and Treatment

Photoaging is the consequence of chronic exposure to solar irradiation, encompassing ultraviolet (UV), visible, and infrared wavelengths. Over time, this exposure causes cumulative damage, leading to both aesthetic changes and structural degradation of the skin. These effects manifest as rhytids, dyschromia, textural changes, elastosis, volume loss, telangiectasias, and hyperkeratosis, collectively contributing to a prematurely aged appearance that exceeds the skin's chronological age. The hallmarks of photoaging vary significantly by skin phototype. Skin of color tends to exhibit dyschromia and features associated with "intrinsic" aging, such as volume loss, while white skin is more prone to "extrinsic" aging characteristics, including rhytids and elastosis. Moreover, susceptibility to different wavelengths within the electromagnetic spectrum also differs by skin phototype, influencing the clinical presentation of photoaging, as well as prevention and treatment strategies. Fortunately, photoaging-and its associated adverse effects-is largely preventable and, to some extent, reversible. However, effective prevention and treatment strategies require careful tailoring to an individual's skin type. In this review, we summarize molecular mechanisms underlying photoaging, examine its clinical manifestations, outline risk factors and prevention strategies, and highlight recent advancements in its treatment.