One teaspoon of pure caffeine powder delivers about the same jolt as 25 cups of coffee. The Center for Science in the Public Interest hide caption

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The bar at a surprise birthday party for Teen Wolf's Stephen Lunsford, presented by Monster Energy last November in Los Angeles. Todd Williamson/Invision/AP hide caption

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U.S. Army Pvt. Freymond Tyler sleeps on a laptop next to his gun at combat outpost Makuan in Kandahar province, Afghanistan, in 2011. Romeo Gacad/AFP/Getty Images hide caption

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