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Caffeine: The good, the bad and the ugly

Cut the fat. Cut the alcohol. Cut the nicotine. Cut the caffeine? Must you really give up your morning mug to stay healthy? Not according to the latest research. As it turns out, there’s little evidence to back up many of the caffeine scares of recent years.

For a while, coffee was linked to heart disease, but then researchers realized that a lot of coffee drinkers also smoke cigarettes, a major risk factor for cardiovascular disease. Not surprisingly, after adjusting for smoking among coffee drinkers, the connection was found to be nonexistent.

Although compounds in coffee called cafestol and kahweol have been shown to raise LDL (the “bad”) cholesterol levels, filtered brewing techniques remove those compounds. Those who drink espresso, French press or other nonfiltered brews may want to moderate their intake or switch to instant or drip coffees.

What about caffeine and cancer? Since an early study suggested that coffee might be responsible for many cases of pancreatic cancer, java lovers have been wary. But researchers have yet to duplicate the results of that study. As for links with bladder, breast, colon or lung cancer, researchers also have come up empty-handed.

Caffeine has also been fingered as a culprit in osteoporosis. It’s true that caffeine increases the amount of calcium excreted in a woman’s urine. But your caffeine intake would have to be excessive to have a significant effect on bone density. To stay on the safe side, drink a cup of milk for every cup of coffee.

Finally, many women have been told to limit their caffeine intake to avoid fibrocystic breast changes—painful, nonmalignant lumps. While caffeine may aggravate fibrocystic lumps, there is no solid evidence to suggest that it causes them.

Still, caffeine, like any drug, has its share of side effects. Drink more than two cups of coffee a day and you may feel restless, irritable and have trouble sleeping.

Caffeine contributes to heartburn, constipation and diarrhea and irritates stomach ulcers. And people who have abnormal heart rhythms or high blood pressure should limit their intake.

When it comes to a woman’s reproductive system, drinking three or more cups of coffee a day may affect her ability to conceive. In a pregnant woman, it appears to be linked to low-birth-weight babies. However, researchers have yet to prove a link between caffeine and birth defects. If you are pregnant or planning to conceive, discuss caffeine intake with your obstetrician.