UV rays contribute significantly to the aging of skin through a process called photoaging — skin damage caused by prolonged exposure to ultraviolet radiation, especially UV-A and UV-B rays. Here’s how:
How UV Rays Cause Skin Aging:
- Damage to Collagen and Elastin:
- UV radiation penetrates the skin and damages collagen and elastin fibers, which provide structure, strength, and elasticity to the skin.
- When these fibers break down or are improperly formed, the skin loses its firmness and elasticity, leading to wrinkles, sagging, and rough texture.
- Generation of Free Radicals (Reactive Oxygen Species):
- UV exposure causes the formation of harmful molecules called free radicals.
- These free radicals damage skin cells, DNA, and lipids by oxidative stress, accelerating skin aging and impairing cell repair mechanisms.
- Inflammation and Immune Suppression:
- UV radiation triggers inflammation in the skin, which can degrade skin tissue over time.
- It also suppresses local immune responses, reducing the skin’s ability to repair itself and fight off damage.
- Pigmentation Changes:
- UV rays stimulate excess production of melanin, causing age spots, freckles, and uneven skin tone, which are visible signs of aging.
- Thickening and Roughness:
- Chronic UV exposure causes the outer skin layer (epidermis) to thicken unevenly, leading to a rough, leathery appearance.