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Pain relievers

A little caffeine can curb headaches, but in large quantities it can actually cause them, some research suggests. Many pain relievers incorporate caffeine to ease the pain, but if you take more than the label suggests, you could be taking more than you need. Two Excedrin Migraine tablets have 130 milligrams of caffeine, the same as a Starbucks Light Frappuccino with espresso— so stick with the two-tablets-per-24-hours label instructions.

Next: Energy water