The difference between uva and uvb

UVA and UVB are two types of ultraviolet rays in sunlight. They both affect our skin, but their effects and impacts are different. Simply put, UVA is the main factor causing skin aging, while UVB is the culprit causing skin sunburn.

UVA accounts for 95% of ultraviolet rays, with a longer wavelength that can penetrate windows and clouds and penetrate deep into the dermis of the skin. This type of ultraviolet light can damage collagen and elastic fibers in the skin, causing wrinkles and sagging of the skin. Long-term exposure may also increase the risk of skin cancer. Imagine that UVA is like an invisible time machine that quietly accelerates the aging of your skin.

UVB has a shorter wavelength and mainly affects the surface layer of the skin. It is the main cause of sunburn, especially in the summer when the sun is strong. UVB can directly damage the DNA of skin cells, causing redness, peeling and even sun spots. Although UVB only accounts for 5% of ultraviolet rays, it has stronger energy and can cause damage to the skin in a short period of time.

How can we protect ourselves from these two types of ultraviolet rays? Using a broad-spectrum sunscreen is a good choice, as it can protect against both UVA and UVB. Choose a sunscreen with an SPF value of 30 or above, which can effectively block UVB, while the PA value is a measure of the sunscreen's ability to resist UVA, with PA+++ being a higher level of protection. Remember to apply it 15 minutes before going out, and reapply every two hours.

Physical protection is also important. Wearing wide-brimmed hats, sunglasses, and long-sleeved clothing are good ways to reduce direct exposure to UV rays. Choosing a parasol or seeking shade can also provide additional protection for your skin.

Knowing the UV index in the weather forecast can help us better plan our outdoor activities. When the UV index is high, try to avoid prolonged exposure to the sun between 10 am and 4 pm.

Through these methods, we can effectively reduce the damage of UVA and UVB to the skin and maintain young and healthy skin. Remember, sun protection is not only for beauty, but also an investment in health.