Caffeine Can Make You More Alert There's
no magic bullet to boost IQ or make you smarter -- but certain
substances, like caffeine, can energize and help you focus and
concentrate. Found in coffee, chocolate, energy drinks, and some
medications, caffeine gives you that unmistakable wake-up buzz --
though the effects are short term. And more is often less: Overdo it on
caffeine and it can make you jittery and uncomfortable.
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