Caffeine: A mixed bag
Surprise! It may protect against certain diseases. But be careful.
Chances are good that while you're reading this you're drinking coffee. Millions of Americans can't quite function without a daily fix. A recent study shows nearly 90% of adults and at least three-quarters of kids have caffeine daily. Since 1977, the numbers have increased slightly for adults but dramatically for children. Although our grandparents preferred coffee and tea, our generation goes more for coffee and colas. For kids, sodas top the list.
Why so much caffeine? Students, doctors and others who need to be up for long hours rely on it to stave off sleep. Travelers use caffeine to fight jet lag. Some athletes think it enhances performance. In recent studies, caffeine may be associated with reduced risk of gallbladder disease, type 2 diabetes, symptoms related to Parkinson's disease, and even liver cancer.
Look over the list below. If you are someone who won't do well with extra stimulants in your life, caffeine probably isn't for you. For others, it's wise to keep it in check. As a general rule, limit your intake to around 200 milligrams a day (about the amount of caffeine in two cups of regular coffee, three cups of black tea or four cans of cola).
Tedd Mitchell, M.D., is medical director of the Cooper Clinic's Wellness Program.
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Review the facts
Caffeine is a drug. It's the most commonly consumed drug in the world, and while most consumers have no significant problems with caffeine, it does have chemical effects on the body.
Caffeine may be hidden. Most of us know the "big three" -- coffee, teas, colas -- but are unaware of other caffeine sources, like chocolate. Many labels don't list caffeine contents, making it difficult to track. For example, did you know that a Sunkist orange soda has about as much caffeine as a Coca-Cola?
Caffeine is difficult to measure. Coffee tends to contain the most, followed by teas and soft drinks. But there are so many varieties, sizes and strengths of coffee that you can no longer make simple statements about how much is in your favorite cup of joe.
Caffeine is a diuretic. It makes the body produce more urine than normal. That can be a problem if you already have urinary difficulties -- bladder control issues, prostate problems, etc.
Caffeine is a stimulant. That's why some use it to improve mental alertness or to combat fatigue. But that's also why its users can develop insomnia, jitteriness, nervousness -- even heart palpitations or high blood pressure.
Caffeine is a tough habit to kick. Caffeine withdrawal can bring on headaches, sleepiness, fatigue, sadness, irritability, inability to concentrate, nausea, and muscle aches and pains. These symptoms generally pass in a few days. If you want to kick caffeine, avoid problems by slowly decreasing your intake over several days or a few weeks. Because withdrawal's effects are real and potentially disruptive to daily life, some psychiatric researchers believe caffeine withdrawal should be included in the next Diagnostic and Statistical Manual of Mental Disorders (DSM), the psychiatrist's "bible" for determining mental disorders.