MONDAY, June 16 (HealthDay News) - Good news for coffee lovers: Drinking up to six cups a day of caffeinated or decaffeinated coffee daily won't shorten your life span, a new study shows.

In fact, coffee might even help the heart, especially for women, the researchers found.

"Our results suggest that long-term, regular coffee consumption does not increase the risk of death and probably has several beneficial effects on health," said lead researcher Dr. Esther Lopez-Garcia, assistant professor of preventive medicine at the Autonoma University in Madrid, Spain.

Her team published its findings in the June 17 issue of the Annals of Internal Medicine.

Lopez-Garcia stressed that the findings may only hold true only for healthy folk. "People with any disease or condition should ask their doctor about their risk, because caffeine still has an acute effect on short-term increase of blood pressure," she said.

In the study, the Spanish team looked at the relationships between coffee drinking and the risks of dying from heart disease, cancer, or any cause in almost 42,000 men who participated in the Health Professionals Follow-Up Study and more than 84,000 women who had participated in the Nurses' Health Study. At the study start, all participants were free of heart disease and cancer.

The participants completed questionnaires every two to four years, including information about their coffee drinking, other dietary habits, smoking and health conditions. The research team looked at the frequency of death from any cause, death due to heart disease, and death due to cancer among people with different coffee-drinking habits, comparing them to those who didn't drink the brew. They also controlled for other risk factors, including diet, smoking and body size.

The researchers found that women who drank two or three cups of caffeinated coffee daily had a 25 percent lower risk of death from heart disease during the follow-up (from 1980 to 2004) than non-drinkers. Women also had an 18 percent lower death risk from a cause other than cancer or heart disease compared with non-coffee drinkers.

For men, drinking two to three cups of caffeinated coffee daily was a "wash" -- not associated with either an increased or a decreased risk of death during the follow up, from 1986 to 2004.

The lower death rate was mainly due to a lower risk for heart disease deaths, the researchers found, while no link was discovered for coffee drinking and cancer deaths. The relationship did not seem to be directly related to caffeine, according to the researchers, since those who drank decaf also had a lower death rate than those who didn't drink either kind of coffee.

In the past, studies have come up with mixed results on the health effects of coffee, with some finding coffee increased the risk of death and others not.

More recently, research has found coffee drinking linked with a lower risk of type 2 diabetes and some cancers, and preventing the development of cardiovascular disease, Lopez-Garcia said.

The strength of her current study, she said, includes the large number of participants and long follow-up period.

While the study is interesting, it does have its shortcomings, said Dr. Peter Galier, an internal medicine specialist, former chief of staff at Santa Monica UCLA and Orthopedic Hospital and associate professor of medicine at the University of California Los Angeles' David Geffen School of Medicine.

Self-reporting is one shortcoming, he said, because people may have under- or over-reported their coffee consumption, for instance.

"I think what this study tells us is not so much that coffee is the answer to everything," he said. But, rather, that some compounds, such as the antioxidants found in coffee, may be healthy.

Galier's advice for consumers: "I would tell them to weigh the subjective risk of their coffee consumption," he said. For instance, "if they love coffee, but it makes them jittery, and they can't sleep, the need to adjust it," he said. "Look at your symptoms," he tells patients. "If decaf is no problem, I wouldn't put a limit on that."

The research was funded by grants from the U.S. National Institutes of Health.

More information

There's more on coffee at the American Dietetic Association.