What protects the skin during exposure to UV rays?

Melanin is a natural pigment found in the skin that plays a crucial role in protecting against UV radiation. When the skin is exposed to UV rays, melanin production increases as a defense mechanism, leading to tanning. This increased melanin content absorbs and dissipates UV radiation, reducing the risk of DNA damage that can lead to skin cancer.

Oils, while they can provide some level of moisture to the skin and may help with skin barrier function, do not specifically protect against UV radiation. Water, although essential for skin hydration, does not offer protection against UV rays either. Vitamins, though they have various health benefits, do not form a protective barrier or absorb UV light like melanin does. Consequently, melanin is the primary substance that provides the most significant defense against UV exposure.