Malcolm Noriega, 35, a consulting engineer from Manchester, used to wake up on weekend mornings with wicked headaches, complete with nausea and a light-sensitivity so intense he had to wear sunglasses indoors.
“The damned things were Tylenol-and ibuprofen-resistant,” he says. “Maybe by afternoon I’d be able to function.”
Finally, friends suggested his problem might be caffeine withdrawal, though he drank only a cup and a half of coffee on workdays. So he started drinking coffee on the weekends and, “presto! My headaches went away. . .it’s like a necessary evil to do this.”
Caffeine is the only drug that’s widely added to food. But whether it should be – and if so, in what amounts and with what labels – is an old battle that’s heating up again.
Last summer, the Center for Science in the Public Interest, a nonprofit advocacy group in Washington, petitioned the US Food and Drug Administration to take another look at the safety of caffeine and to require that products that contain it – including heavily-hyped soft drinks kids love to guzzle – be labelled to reveal how much caffeine they contain.
The amount of caffeine in various products might surprise you. A cup of Starbuck’s coffee ice cream has as much caffeine as half a cup of instant coffee, the public interest group says, while other brands have almost none. A cup of Dannon coffee yogurt has as much as a 12-ounce Coke, while Dannon light cappucino yogurt has none.
The FDA is now mulling it over, but hints its long-time view will prevail: Pregnant women should avoid caffeine or drink it in moderation, but overall “there’s no reason to suspect the status of caffeine should be changed.”
Not surprisingly, that’s what the National Soft Drink Association thinks, and the National Coffee Association as well.
Even caffeine researcher Roland R. Griffiths, a psychopharmacologist at Johns Hopkins School of Medicine, says there’s “no life-threatening health risk associated with daily consumption” – a good thing, given that 85 percent of the population consumes at least 200 milligrams of the stuff a day.
Though lay people often use the word “addicted” to describe their love-hate relationship with the stimulant, caffeine is “very unlike our classic drugs of abuse,” he adds, though it can produce dependence – and withdrawal symptoms like Noriega’s – at doses as low as 100 mg a day. That’s just one 5-ounce cup of coffee or a couple of Diet Cokes.
But if caffeine won’t kill you, neither is it harmless. At 100 to 200 mg a day, your mood may be mildly enhanced, says Dr. Andrea Seek, a Lahey Clinic psychiatrist. But at 300 mg – two small cups of coffee – you may feel anxious. At 1,000 mg – that’s ten cups – your speech may ramble and you may get heart palpitations. At 10,000 mg, you may get seizures.
And because caffeine stays in the body up to 10 hours, it can cause insomnia, unless you’re tolerant to its effects.
So this part is easy: If you’re prone to anxiety, panic attacks or insomnia, you may want to eschew the brew, because caffeine can make things worse. Ditto if caffeine makes your heart beat crazily, though a recent review of data showed that even five to six cups of coffee a day did not increase the frequency or severity of arrhythmias.
But what of the stickier wickets like cancer, fibrocystic breast disease, cardiovascular disease, osteoporosis, and reproductive problems?
So far, the research “has identified no significant health hazard from normal caffeine consumption,” says the International Food Information Council, an industry group, in a brochure approved by American Academy of Family Physicians.
But some folks – and Science in the Public Interest – aren’t convinced. A point by point analysis is in order:
– Cancer. More than a decade ago, a New England Journal of Medicine study suggested a link between coffee and pancreatic cancer. That has since been shown to be “not true,” says the FDA.
Several years ago, an analysis in the British medical journal Lancet of data pooled from 35 studies examined the putative link with bladder cancer – and found none. Two large studies in Norway and Hawaii also found no link between coffee and cancer. The bottom line? There’s no known link between cancer and caffeine.
– Fibrocystic disease (benign breast lumps). Anecdotes to the contrary, researchers have found no link with caffeine. (They’ve found no link with breast cancer, either.)
– Cardiovascular disease. Years ago, some data suggested that coffee could raise blood pressure and cholesterol, but this was in Scandinavia, where coffee is made by boiling. In studies with coffee that is filtered – as it usually is in America – there was no such effect, probably because filtering removes the bad stuff (cafestol and kahweol) from the oils in ground coffee.
Coffee can produce a transient boost in blood pressure in people with normal pressure, notes Dr. Barry Woods, a Lahey Clinic cardiovascular specialist. But a review of 17 studies found no persistent increase.
And considerable data – including two Harvard studies of nurses and other health professionals – found no link to heart disease even among people who drank as much as five cups of coffee a day. “It’s a dead issue,” says Dr. Meir Stampfer, a Harvard epidemiologist.
– Osteoporosis. While data are mixed, some studies suggest caffeine leads to loss of calcium from bones and an increased risk of fractures. This can be offset by drinking milk.
– Infertility. Studies are mixed here, too. A 1990 study of nearly 3,000 women by researchers at Harvard Medical School and the federal Centers for Disease Control found no link between caffeine and fertility. But a 1995 Johns Hopkins study of 2,500 women suggested that drinking more than 300 mg a day of caffeine reduced the odds of conception by 17 percent per cycle.
– Miscarriage. There are four studies on this, in which pregnant women who drank coffee were followed to see if problems turned up later. Two found no effect of caffeine and two found a somewhat higher miscarriage rate at 150 to 300 mg of caffeine a day.
– Birth defects. Three studies involving more than 15,000 women have found no effect. Even the Science in the Public Interest folks concede there’s little evidence linking caffeine to birth defects.
However, three studies found consumption of more than 300 mg a day of caffeine can lead to lower birth weight.
Taken together, all this means that caffeine doesn’t exactly rank as a leading health problem. But it can feel that way, especially when you try – and fail – to quit. It may help to realize that the DSM-IV, the psychiatrists’ bible, lists caffeine withdrawal as a genuine disorder. (Caffeine intoxication is, too.)
Often, caffeine researchers say, the real problem is that people think they have a handle on everything that contains caffeine and they don’t.
That’s because it’s not just in foods, as a natural ingredient or additive, but in medications, too, from over-the-counter wake-up remedies like Vivarin (200 mg per tablet) and painkillers like Excedrin (130 mg per two tablets) to prescription headache pills like Fiorinal and Esgic.
People also underestimate how much caffeine they take in, especially with mugs of coffee, which may contain twice the caffeine of a cup, says Dr. Fred Sheftell head of the New England Center for Headache in Stamford, Conn.
Some people, especially those who have headaches, including migraines, may also get caught in a vicious cycle because some caffeine is a double-edged sword. It boosts the effectiveness of pain medications, but withdrawal can also trigger headaches.
For Malcolm Noriega, the solution to the withdrawal problem is to increase intake so it’s constant every day. If you want to quit instead, you have to do it slowly – by 100 to 160 mg – roughly a cup of coffee – every two or three days. If you’re not drinking that much to start with yet still have withdrawal because you’re highly sensitive, decrease by a half cup every four or five days.
If your energy sags along with your intake, the answer is not caffeine, says Sheftell. It’s exercise: “Get those endorphins going.”