Caffeine: the bitter truth
It boosts mood and energy — if you don’t mind being addicted
by Jean Carper
VERY DAY, about 8 in 10 U.S. adults take in caffeine, the world’s most popular psychoactive drug.
“Caffeine is a classic stimulant, producing feelings of increased energy and well-being, decreased sleepiness, more talkativeness and sociability, and a better ability to concentrate,” says Roland Griffiths, Ph.D., a prominent caffeine researcher at Johns Hopkins University.
It’s also mildly addictive. If you take in caffeine regularly, you’re apt to feel lousy if you miss your fix.
Here’s the latest scientific word:
It’s OK for most.
As drugs go, caffeine is relatively benign. But restrict caffeine if you have anxiety, insomnia, panic disorder, heart arrhythmias, tachycardias or palpitations, or if you’re pregnant, Griffiths advises. Some experts say avoiding caffeine can lower blood pressure.
A mere cup of tea with just 60 milligrams of caffeine (about half the amount in coffee) can speed up mental functioning, British research finds. Subjects showed faster response times on mental tests within minutes of drinking a cup of caffeinated tea, vs. decaf. In other British research, a cup of tea or coffee in the morning, early afternoon and early evening preserved alertness and good mental functioning all day, compared with plain water.
More than half of regular caffeine users are apt to suffer withdrawal if they quit abruptly, says Griffiths. You can suffer after giving up just one cup of coffee a day. His new research also finds it takes only three days of taking in 300mg a day to get hooked. Kids are vulnerable, too, says University of Minnesota researchers. Daily for two weeks, 8- to 12-year-olds were given the caffeine in three to five soft drinks. Then the caffeine was cut off. Within 24 hours, the kids’ mood and mental performance deteriorated. They had slower reaction times and shorter attention spans. Symptoms lasted two weeks.
Without a caffeine fix, most regular users suffer mild to severe headaches within 12 to 36 hours. Also common: depression, sleepiness, even nausea and flu-like symptoms. If you cut down, do it gradually over a week or so, Griffiths advises. Taking in as little as 25mg daily — the amount in 1.5 ounces of coffee or 6 ounces of cola — can ward off headaches, he finds.
Caffeine vs. cancer?
There’s little evidence caffeine promotes cancer, except possibly bladder cancer. In fact, recent Japanese research suggests caffeine alters hormones in ways that may reduce the odds of breast
cancer. New Swiss research finds coffee drinkers have a 27 percent lower risk of colon cancer. A study at Harvard suggested drinking four or five cups of coffee a day cuts the risk of colorectal cancer by 24 percent.