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

itoggle caption The Center for Science in the Public Interest

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

itoggle caption Romeo Gacad/AFP/Getty Images