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How Does Sunscreen Work?

By August 17, 2018May 11th, 2023Skin Care, Skin Care Products

We know that we need to wear sunscreen when outdoors to protect our skin from cancer-causing UV rays. But how exactly does sunscreen protect our skin? Here’s what you need to know about how this substance works to ward off sun damage.

Sun-Blocking Chemicals


Most sunscreens contain a combination of organic and inorganic chemicals. The inorganic substances, including minerals such as zinc oxide and titanium dioxide, actually reflect the UV rays. Organic chemicals used in sunscreen, including avobenzone and oxybenzone, possess chemical bonds that absorb and release the radiation emitted by the sun, preventing it from entering the skin cells.

The Role of Sun Protection Factor

Sun Protection Factor (SPF) is a measure of how well the sunscreen formula blocks UVB rays, which cause sunburn and certain types of skin cancer. UVA radiation raises cancer risk and leads to signs of aging such as fine lines, wrinkles, and dark spots. For optimal protection, look for a broad-spectrum formula that blocks both UVA and UVB rays. An SPF 15 formula will block 93 percent of the sun’s rays, while an SPF 30 formula protects you from 97 percent. No formula provides perfect protection.

Proper Sunscreen Use

Sunscreen is more effective when used as directed. Use at least an ounce of sunscreen for each application and reapply sunscreen every two hours or after swimming. In addition to sunscreen use, maximize your protection with a wide-brimmed hat, sunglasses, and lightweight clothing that covers the skin. Wear sunscreen every day, even when it’s cloudy or you don’t expect to go outdoors. After all, UV rays can even penetrate the windows of your car.

The Dermatology Clinic in Baton Rouge offers a full spectrum of skin care options, including laser treatments to mitigate the effects of sun damage. Schedule an appointment with our experienced team for a skincare consultation at one of our three convenient area locations. If you’re looking for a new skincare regimen for the summer, you can also shop our store for high-quality sun protection options.