Which rays are characterized as the aging rays, known for penetrating the reticular dermis?

UVA rays are primarily responsible for skin aging, as they penetrate deep into the skin, specifically the reticular dermis. These rays can cause significant damage to collagen and elastin fibers, leading to premature aging characteristics such as wrinkles and fine lines. UVA rays account for approximately 95% of the sun's ultraviolet radiation that reaches the Earth and have a longer wavelength than UVB rays, which allows them to penetrate the skin more deeply.

In contrast, UVB rays primarily affect the outer layer of the skin and are mainly responsible for producing sunburns. Infrared rays and visible light do not have the same impact on skin aging as they are not as effective in penetrating the skin layers to the extent that UVA rays do. Recognizing the harmful effects of UVA rays is crucial for developing proper sun protection strategies to mitigate skin aging and related concerns.