WASHINGTON, Aug. 16 (Xinhua) -- Heavy coffee consumption is associated with an increased death risk in people under 55 years old, a new study has shown.
The study, published in the journal Mayo Clinic Proceedings, found a statistically significant 21 percent increased mortality in those drinking more than 28 cups of coffee a week or 4 cups of coffee a day.
Based on age groups, the risk of death from all causes rose by more than 50 percent for men and women younger than 55 but no adverse effects were found in heavy coffee drinkers aged over 55, it said.
In this study, researchers from the University of South Carolina examined the coffee consumption of more than 43,000 individuals aged between 20 and 87 years from 1971 to 2002. During the 17-year median follow-up period, more than 2,500 participants died.
It found that younger men had a trend towards higher mortality even at lower consumption, but this became significant at about 28 cups per week where there was a 56 percent increase in mortality from all causes.
Younger women who consumed more than 28 cups of coffee per week had double the risk of dying from all causes than those who did not drink coffee, the study said.
"For those drinking high amounts, there should be some caution, as this dose was associated with at least a signal for increased total mortality in this large study, especially in those under 55 years of age," Xuemei Sui from the University of South Carolina in Columbia and co-author of the study told Xinhua on Friday.
Coffee has long been suspected to contribute to a variety of chronic health conditions, although earlier studies on coffee consumption in relation to deaths from all causes and deaths from coronary heart disease are limited, and the results are often controversial.
"No organization has specific recommendations for coffee drinking. Lots of out there are based on published studies which yet reach a definite conclusion," Sui said. "My review is that it is safe to drink low doses (1 to 2 cups and probably 2 to 3 cups per day) of coffee, with even some potential benefits of the low dose."
"Really moderation is KEY. Avoid excess drinking coffee," Sui added.