Most Americans in need of a jolt of energy reach for a stimulant. Whether we're getting our fix from an espresso maker, a teapot, or a vending machine, caffeine is the drug of choice for people who need to feel fired up fast. Caffeine boosts energy by stimulating the central nervous system and increasing the heart rate and blood pressure. But this pick-me-up can also let you down. Sensitive people tend to feel jittery and anxious, not jazzed, after a cup of coffee or a can of soda. Caffeine can also sabotage your sleep, setting up a bad pattern: use caffeine, sleep poorly, need more caffeine the next day to compensate. For some people, caffeine is addictive; the slump you feel when its effects wear off compels you to consume more -- turning it into a crutch.
The obvious solution to a dependency on caffeine is to consume less of it. But as anyone who has tried to go cold turkey knows, withdrawal symptoms like throbbing headaches, nervousness, irritability, and fatigue are no picnic. A better way to cut back? Gradually decrease the amount you consume -- drink one fewer cup of coffee every day, for example. It also helps to know how much caffeine is in common foods and beverages: A cup of coffee contains 135 mg, a cup of black tea has up to 70 mg, a Red Bull has 80 mg. If you still savor a steaming beverage once or twice a day, try green tea. It has less caffeine than coffee (25 to 40 mg total) and is rich in antioxidants.