Skin cancer is the most common cancer in the United States—and one of the most preventable. Protecting your skin from carcinogenic rays of the sun —through daily use of sunscreen, seeking shade, and wearing sun protective clothing—is essential to preventing skin cancers.

Sunscreens are products that combine several ingredients that shield the skin from the sun’s harmful ultraviolet rays. Two types of ultraviolet radiation-UVA and UVB-can damage the skin and increase the risk of skin cancer. Sunscreens vary in their ability to protect against UVA and UVB rays. They also vary in their SPF or “sun protection factor”. SPF measures the ability of a sunscreen to prevent UVB rays from penetrating the skin. If a sunscreen has an SPF of 30, then it will take 30 times longer for your skin to burn than it would if you did not use sunscreen.

Use a sunscreen with SPF 30 or higher that is also broad-spectrum, meaning it protects you from both UVA and UVB rays. Sunscreen should also be water-resistant, especially when used during outdoor activities, such as sports and swimming. Reapply sunscreen every 2 hours and after getting wet.

What’s your sunscreen IQ? Test your sun protection knowledge with our quiz below:

  • True or False

  • Multiple Choice

1 Autier (September 22, 2009) Sunscreen Abuse for Intentional Sun Exposure. British Journal of Dermatology; 161; s3.

2 Wang, Steven. (May 24, 2018). Ask the Expert: Does a High SPF Protect My Skin Better? Accessed online

3 Godar DE, Urbach F, Gasparro FP, van der Leun JC. UV doses of young adults. Photochem Photobiol 2003; 77(4):453-7.

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