everything you know about spf is wrong
You know that healthy, smooth, even-toned skin is the trade-off for spending time in the sun, so you act accordingly to protect it. Surprisingly, many people who think they have taken appropriate measures to guard their skin have inaccurate, outdated information.
Here, Dermalogica skin experts dispel three shockingly common sun protection myths:
Myth: A high SPF will keep skin safe from the sun's harmful rays
Sun Protection Factor, or SPF, merely indicates how long it will take for UVB rays to cause sunburn. So, skin wearing SPF 15 will take 15 times longer to redden than it would without it. This has nothing at all to do with UVA rays, which penetrate the skin more deeply, and play a major part in accelerating the signs of skin aging and generating skin cancer.
To protect your skin from both UVA and UVB rays, make sure your product is labeled "Broad Spectrum," meaning it contains a combination of ingredients known to protect skin against the destructive duo.
To ensure thorough Broad Spectrum protection, opt for a cream or lotion over a difficult-to-gauge spray and apply an ounce (about a shot glass full) to your body and a teaspoonful to your face 15 minutes before going outside, being sure to reapply every two hours (or after swimming or exercising).
Myth: A base tan will protect me from the sun.
There is no such thing as a safe tan. A suntan is what happens when your skin reacts to being harmed by UV exposure. Your cells respond to the affront by producing more melanin (pigment), so your skin darkens.
Myth: It's winter and it's cloudy out. I don't need sunscreen!
Sun damage doesn’t only happen during the summer months or while you're at the beach. The sun's rays don't care about the mercury reading. Photo damage and UV exposure (which causes aging) occur from exposure to daylight. It can even happen through windows! This is why protecting the skin every day is imperative.