Our moms weren't kidding around when they demanded we slather on the sunscreen.

Unprotected sun exposure leads to leads to leathery, wrinkled skin that bruises easily and increases your chances of skin cancer. But while we've heard this over and over again, actually seeing the negative effects might be the best wake-up call.

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Videographer Thomas Leveritt asked people on the street to take a look at themselves under ultraviolet light, exposing sun damage beneath the skin that hasn't revealed itself yet. But it's when Leveritt offers his subjects sunscreen that we see the true effectiveness of that greasy stuff.

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