Drinking up to six cups of coffee a day might not lead to early death but rather help the heart, especially for women, a new study has showed.
The findings were published in the June 17 issue of the Annals of Internal Medicine, published by the American College of Physicians.
"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 leading researcher Dr. Esther Lopez-Garcia, assistant professor of preventive medicine at the Autonomous University of Madrid, Spain.
Lopez-Garcia stressed that the findings may only hold true for healthy people.
"People with any disease or condition should ask their doctor about their risks, because caffeine still has an acute effect on short-term increase of blood pressure," she said.
The Spanish team looked at data of nearly 42,000 U.S. men who participated in the Health Professionals Follow-Up Study from 1986 to 2004 and more than 84,000 U.S. women who had participated in the Nurse Health Study from 1980 to 2004 to assess relationships between coffee drinking and the risks of dying from heart disease, cancer, or any cause. All participants were free of heart disease and cancer at the start of the study.
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 with other risk factors, including diet, smoking and body size under control.
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 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.
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 decaffeinated coffee 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 to a lower risk of type 2 diabetes and some cancers while preventing the development of cardiovascular disease, Lopez-Garcia said.
The strength of her current study, she said, is based on the large number of participants and long follow-up period.