Ultraviolet (or UV) radiation damages the skin by weakening elastic collagen fibers and by preventing stem cells from rejuvenating the injured area. It also causes free radicals to damage the DNA, which can lead to cancer.
Interestingly, UV radiation comes in many forms, and we can see only a small spectrum. Other animals see things that we don't (and vice versa), which explains why they are attracted to apparently dull objects or have strange colors themselves. Some animals, including birds, reptiles, and insects such as bees, can see into the near ultraviolet. Many fruits, flowers, and seeds stand out more strongly from the background in ultraviolet wavelengths than human color vision. Scorpions glow or take on a yellow to green color under UV illumination. Many birds have patterns in their plumage that are invisible at usual wavelengths but observable in ultraviolet, and the urine of some animals is much easier to spot with ultraviolet.

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Ultraviolet (UV) radiation is electromagnetic energy from the sun. Most of the sun's UVA rays and about 10% of its UVB rays reach the Earth. In small amounts, UV radiation is good for you. It helps your body produce vitamin D. However, too much exposure to UVA and UVB radiation can damage the skin over time. UVA radiation penetrates deep into the skin, causing premature aging and leaving damage behind that can lead to skin cancer. UVB rays cause the skin to become sunburned, and they can also increase your risk for skin cancer. To avoid sun damage, wear a daily sunscreen that protects against both UVA and UVB radiation. For more information about sun protection, consult a dermatologist.
Use a sunscreen and wear protective clothing to safeguard your skin from the sun’s harmful rays.
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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.