Collagen is the protein that holds your skin together and gives it strength and elasticity. This fibrous protein forms in the middle, or dermal, layer of your skin, starting as individual fibroblast cells that come together to form a protective fiber mesh. Although in total there are 12 types of collagen, SmartSkinCare.com notes that types 1 and 3 are the most important to your skin. Repeated exposure to ultraviolet sunlight that penetrates your skin can damage or alter collagen production.
Identification
Ultraviolet sunlight consists of UVA, B and C rays. Of these, only UVA rays are capable of penetrating through the dermal skin layer and contributing to skin aging and wrinkling by destroying or altering collagen. UVA rays, also called tanning rays, make up about 95 percent of the ultraviolet light that reaches the earth.
Significance
UVA rays affects collagen through a process called photoaging. Although the net effect these rays have on your skin depends on factors such as skin color and degree of exposure, even limited exposure over a long period can cause collagen damage.
Process
Damage occurs as repeated exposure begins to weaken mature collagen fibers. At the same time, UVA rays cause elastin, another fibrous skin component, to reorient itself from its normal position to a position parallel to the surface of your skin and begin to reproduce in unusually high amounts. The presence of this abnormal elastin causes secretion of enzymes called metalloproteinases. These enzymes destroy collagen by, in effect, chopping it into small pieces.
Effects
The most significant effect this process has on your skin is cumulative collagen degradation. Eventually your skin loses the ability to repair itself. The loose, wrinkled, aged look you observe on sun-damaged skin is the ultimate result.
Prevention
You can counteract the effects of photoaging with photoprotection from UVA rays. Photoprotection includes both physical protection, such as clothing, an umbrella or tent, as well as chemical protection, such as sunscreen or sunblock. Recommendations regarding chemical protection include using a broad-spectrum sunscreen that includes UVA and UVB protection at an SPF, or sun protection factor, of 30 or higher. In addition to preventing collagen degradation, this helps protect against skin cancer.
References
- University of Maryland Medical Center: Dermatology -- Anatomy of the Skin
- Smart Skin Care: Skin Collagen: More Than Meets the Eye
- Skin Cancer Foundation: UV Information -- Understanding UVA and UVB
- Skin Care Physicians: Causes of Skin Aging
- Skin Science: Cutaneous Disorders -- Dermal Disorders
- Skin Care Physicians: Protection against Photoaging
