What damage can the skin take from the sun?
The main cause of skin aging is the sun’s rays! All skin sections – epidermis, corium and subcutaneous fatty tissue – age due to ultraviolet light. The UV rays release reactive oxygen compounds (ROS) – see also oxidative stress. This leads, among other things, to DNA strand breaks. Furthermore, toxic photoproducts are formed which lead to skin aging as well as to an increased risk of skin cancer. Matrix metalloproteinases (MMPs) are responsible for this. The wrinkles of exogenous skin aging are very deep, because the loss of elasticity is immense. In addition, the skin looks leathery and has irregular pigmentation. Especially sun-exposed skin areas such as the face or hands age prematurely.
Excessive and incorrect sunbathing causes the skin to age more quickly and become wrinkled. In severe cases, the so-called “landman’s or sailor’s skin” develops: the skin becomes thicker and leathery. It loses elasticity because collagen and elastin melt like snow in the spring sun. In addition to skin damage, pigmentary disorders and chronic degenerative changes often occur, as well as skin carcinomas (actinic keratosis; basal cell carcinoma (light skin cancer) or squamous cell carcinoma), favored by chronic dermatitis actinica (inflammatory skin changes caused by light and UV rays).
What is light dermatosis?
Light exposure is the triggering factor of polymorphous light dermatosis. The exact cause of polymorphous light dermatosis is not known. Recent studies suggest that immune regulation is disrupted after UV exposure. About 75 % of the affected persons show an exclusive UV-A sensitivity. 15% show UV-A/B sensitivity.
It has been observed that polymorphous light dermatosis also occurs as a result of sun exposure behind window glass.
Light dermatosis is manifested by small red, itchy pustules, for example on the décolleté, shoulders and forearms. Once you have experienced light dermatosis, it can recur and get worse each time.
If you want to go out in the sun, slowly accustom the skin to the sun and protect the affected skin areas with a special sun blocker with at least sun protection factor 30, which contains both a UV-A and a UV-B filter.
For more information on light dermatosis, see “Polymorphous light dermatosis.”
