Photoaging is the premature breakdown of skin cells due to cumulative exposure to ultraviolet radiation from the sun. Unlike so-called “natural” or chronological skin aging, photoaging causes the skin to become coarse, thickened, wrinkled, and irregularly pigmented. Photoaging is the single greatest factor causing prematurely aged skin.Read more: What is skin aging?
On the surface, photoaged skin typically has larger, more visible pores, and there may be a tendency to develop cysts, benign growths like seborrheic keratosis, and pre-cancerous or cancerous lesions. Malignant lesions are typically found on chronically exposed areas of the skin (such as the face, hands and neck), and include squamous and basal cell carcinomas, and melanomas.
The most pronounced effect of sun exposure is found in the deeper, or dermal layer of the skin, where connective tissue called collagen breaks down, creating wrinkles and sagging.
While deep wrinkles cannot be eliminated without plastic surgery, topical treatments with vitamin A derivatives like tretinoin can reverse some photoaging, smoothing fine wrinkles and improving skin tone and texture.
The best defense against photoaging remains avoiding excessive exposure to the sun, and using a sunscreen with a high SPF, or sun protection factor.
Siddharth Mukherjee,1 Abhijit Date,2 Vandana Patravale,3 Hans Christian Korting,4 Alexander Roeder,4 and Günther Weindl. Retinoids in the treatment of skin aging: an overview of clinical efficacy and safety. Clin Interv Aging. 2006 December; 1(4): 327–348