What causes sunburn and accelerates aging of the skin?

Sunburn and accelerated aging of the skin are primarily caused by ultraviolet (UV) light from the sun. This type of light provides sufficient energy to break bonds within molecules, particularly in the DNA and other essential components of skin cells. When UV light strikes the skin, it can cause direct damage to the DNA or create free radicals, leading to inflammation and cellular damage that manifests as sunburn.

Over time, continued exposure to UV light results in cumulative effects, such as wrinkles, loss of skin elasticity, and changes in skin texture and color, often referred to as photoaging. This process is fundamentally linked to the ability of UV light to penetrate the skin and induce these damaging effects, demonstrating its role in both immediate and long-term skin damage.

In contrast, infrared rays do not carry sufficient energy to break molecular bonds in the same way UV light does, and visible light exposure and cold weather do not have the same damaging effects on the skin structure or lead to sunburn and the specific type of aging associated with UV exposure.