How do UVB rays differ from UVA rays?

UVA and UVB rays are both types of ultraviolet radiation emitted by the sun, but they have different characteristics and effects on the skin. The statement that UVA rays are deeper and reach into the subcutaneous layer is accurate.

UVA rays penetrate the skin more deeply than UVB rays, reaching the dermis and even affecting the deeper layers of skin tissue. This deeper penetration can lead to long-term skin damage, including photoaging and increased risk of skin cancers over time. UVA rays are known to contribute to the formation of wrinkles and age spots by damaging collagen and elastin fibers in the skin.

In contrast, UVB rays primarily affect the outer layer of the skin (epidermis), causing immediate reactions such as sunburn. They are responsible for triggering the production of vitamin D but are also a major contributor to skin cancer due to their capacity to cause direct DNA damage in skin cells.

Understanding the differences between UVA and UVB rays is crucial for effective sun protection and skin health management.