Uploaded June 2012 | Updated September 2026, 16 hours ago

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The first day of summer is June 20th! To celebrate, we're kicking off a trio of summer-themed episodes with a video that explains the chemistry of sunscreen.

Whether you have dark or light skin, the truth is that sun exposure can lead to sunburn, premature aging, and skin cancer. Fortunately, using sunscreen properly can help protect your skin all summer long.