Sunscreen and UV 101: What you need to know!

We talked about what SPF and PA in sunscreens (CLICK HERE) and when to use sunscreens (CLICK HERE).

Broad spectrum sunscreens with SPF and PA are important in protection against photo aging and skin cancer.   Today we know  excess exposure to UVA and UVB rays can damage the skin. The only way to know about whether your sunscreen protects against UVA and/or UVB is to know the ingredients and which rays they would protects against.

What are UVA and  UVB?

The 95% of the rays that reach to earth are UVA (Ultraviolet A). UVA is around during daylight and all throughout the year.  Short (UVA2: 320-340 nm) and long wavelength (UVA1: 340-400 nm) UVA rays can penetrate through clouds and glass. UVA rays can penetrate deeper in to the skin compared to UVB , which causes photo aging of the skin and wrinkles.

UVB causes redness and sun burn and damages the top superficial epidermal layers of the skin.  The intensity of UVB rays changes with season, location and time. The wave length of UVB is at 280 to 320 nm and these rays cannot penetrate through glass.

In summary, UVA penetrates to deeper layers , whereas UVB damages the top layer of the skin.

UV filters that protects against UVA and  UVB

UV filters are active ingredients in sunscreens, which protects you from the sun. The majority of UV filters are chemical. They establish a protective barrier over the skin and absorb UV rays thus preventing UVA/UVB penetration to the skin. Physical or mineral sunscreen active ingredients reflects UV rays. Sunscreen products usually have a combination of chemical and mineral sunscreen actives to provide maximum protection.

The following table lists the UV filters and the type of UV protection.

Please always use a broad spectrum sunscreen and if you have skin problems see your lovely dermatologist.

:)

References

Lautenschlager, S, HC Wulf, and MR Pittelkow. “Photoprotection.” Lancet. 370(2007): 528-37.

Seité S, Reinhold K, Jaenicke T, Brenden H, Krutmann J, Grether-Beck S. Broad-spectrum moisturizer effectively prevents molecular reactions to UVA radiation. Cutis. 2012 Dec;90(6):321-6.

Fourtanier A, Moyal D, Seite S. UVA filters in sun-protection products: regulatory and biological aspects. Photochem Photobiol Sci. 2012 Jan;11(1):81-9.

Dip not: Bu makale reçete, ilaç, medikal veya tedavi edici tıbbi önerilerin yerine kullanılma amacını taşımamaktadır. Bu nedenle, sağlığınızla ilgili konularda, lütfen profesyonel sağlık personeline danışınız. Tablo veya benzeri bilgileri baska bir yerde kullanmadan once lutfen yazili izin isteyiniz.