This popular drink, worth retail sales of over €54 billion last year, has for some time been the focus of ongoing research as scientists explore the impact it may have on human health.
One recent Japanese study, for example, found that drinking coffee daily could cut the risk of liver cancer, while a second study found no association between drinking coffee or tea, and the risk of colorectal cancer.
For the latest research, scientists at Athens university in Greece endeavoured to shed some light on the effect coffee consumption might have on the human cardiovascular system.
Aortic stiffness and wave reflections are important prognosticators of cardiovascular disease risk.
In a cross-sectional study of 228 healthy subjects - 141 men in their mid 40s and 87 women of the same age - the researchers tracked aortic stiffness, wave reflections and coffee consumption over a one year period.
Wave reflections were evaluated with augmentation index (AIx) and augmented pressure (AP).
Adjustments were made for variables such as consumption of decaffeinated coffee, tea, caffeine containing drinks and chocolate.
Coffee consumption was categorised as none, low (<200 mL/d), moderate (200-450 mL/d), or high (>450 mL/d). A total of 14 per cent of subjects consumed no coffee. 32 per cent were categorised as low, 36 per cent as moderate and 18 per cent as high coffee consumers.
The Greek researchers observed a linear relation between coffee consumption and aortic stiffness. Compared with non coffee consuming subjects, PWV was 13 per cent higher, AIx was twice as high, and AP was 2.4 times as high, in the high-coffee consumption subjects.
"We have shown that caffeine acutely increases aortic stiffness and wave reflections," report the researchers in the June 2005 issue of American Journal of Clinical Nutrition, (Vol. 81, No. 6, 1307-1312).
"Which may increase the risk of cardiovascular disease," they conclude.
Heart disease is the number one global killer.