CAFFEINE

WHAT WE KNOW

• In moderation (a single can of soda, a cup of coffee or tea), caffeine gives a temporary increase in energy and mental alertness. Higher doses of caffeine can cause anxiety, dizziness, headaches, and jitters and can interfere with normal sleep. In very high doses, caffeine is harmful to the body.
• The amount of caffeine needed to affect each person differs. The effects of caffeine begin about 15 minutes after you consume it. On average, the smaller the person, the less caffeine necessary to produce side effects. However, caffeine sensitivity is most affected by the amount of daily caffeine use. People who regularly drink beverages containing caffeine soon develop a reduced sensitivity to caffeine, requiring higher doses of caffeine.
• Caffeine moves through the body within a few hours after it's consumed and is then passed through the urine. Caffeine is not stored in the body, but you may feel its effects for up to six hours if you're sensitive to it.
• Caffeine is addictive and may cause withdrawal symptoms - such as severe headaches, muscle aches, temporary depression, and irritability - for those who abruptly stop consuming it.
• Dehydration is a common side effect of drinking too much caffeine. Although you may think you're getting plenty of liquids, caffeine works against the body in two ways: It has a dehydrating effect on the body's cells, and it increases the need to urinate. It's particularly important for active teens that play sports to drink noncaffeinated beverages each day to avoid dehydration.
• Large amounts of caffeine may cause the body to lose calcium and potassium, causing sore muscles and delayed recovery times after exercise.
• When caffeine is added to foods or beverages in the United States, it must appear in the ingredients list on the label, but manufacturers aren't required to list the amount of caffeine.
• Although the effects of caffeine vary from one person to the next, doctors recommend that people should consume no more than approximately 100 milligrams of caffeine daily. That's about one cup of coffee or two cups of tea a day. If you're taking in too much caffeine, it's a good idea to cut back. Kicking the caffeine habit is never easy, so the best way is to cut back slowly to avoid getting headaches and feel achy and depressed.
• Try cutting your intake by substituting noncaffeinated drinks for caffeinated sodas and coffee. Examples include water, caffeine-free sodas, fruit juices, and caffeine-free sports drinks. Keep track of how many caffeinated drinks you have each day, and substitute one drink per week with a caffeine-free alternative until you've gotten below the 100-milligram mark.
• As you cut back on the amount of caffeine you consume, you may find yourself feeling tired. Your best bet is to sleep, not to drink more caffeine. Feeling tired is just your body's way of telling you it needs more rest. Your energy levels will return to normal in a few days.

 

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