Drinking one to two cups of coffee per day is good for the heart, researchers have found.
A study of elderly people aged between 65 and 100 found those who drank moderate amounts of coffee a day had more elastic blood vessels around the heart.
People with high blood pressure should be encouraged to drink moderate amounts of coffee, the authors said, based on the results.
Previously, opinion has been divided over whether coffee is good or bad for the heart.
The research was conducted by the University of Athens on almost 700 elderly residents of a small island called Ikaria, in Aegean Sea, where more than a third of people live to the age of 90 or more.
The research focused on 485 of the residents who had high blood pressure and tested their blood vessels using a heart scan.
Rigid and tough blood vessels are linked to heart disease and are taken as a warning sign of heart problems in the future.
It was found that the patients who drank one to two cups per day of coffee had greater elasticity in their major blood vessels than those who drank more or none at all.
Most drank traditional strong Greek coffee in small cups of between 25ml and 50ml each.
Dr Christina Chrysohoou, presented the findings at the European Society of Cardiology Congress in Stockholm.
She said: “The study revealed that moderate coffee consumption, between one and two cups per day, is associated with higher values of aortic distensibility when compared with other hypertensive elderly individuals taking less coffee.
“There was no evidence, however, that increasing coffee consumption to three to five cups per day would lead to further improvements in aortic distensibility.”
Higher levels of coffee intake did not improve blood vessel health any further, probably because the extra caffeine, which can restrict blood vessels, cancelled out the beneficial effects, she said.
Dr Chrysohoou said: “The results suggest that drinking coffee in moderation should be encouraged even in elderly hypertensive subjects as it seems that it may improve arterial aging.”
The study took into account other factors that would influence blood vessel health including age, gender, physical activity, body weight and diabetes.
The subjects drank their coffee in cafes with friends in a relaxed atmosphere at the beginning and end of the working day, Dr Chrysohoou said, so the psychological benefits of this may also play a part, she said.
Dr Chrysohoou said the findings also suggested that there might be a link between moderate coffee consumption and lower risks of heart disease, diabetes, high cholesterol, obesity and poor kidney function.
It is thought chemicals in coffee improve heart health by preventing damage caused by oxygen molecules and blocking harmful nitric oxide.
Other nutrients including flavonoids, magnesium, potassium, niacin and vitamin E all combat the harmful effect of oxygen on cells.
Greek coffee is traditionally boiled and not filtered so is higher in these compounds, Dr Chrysohoou said.
The authors said in patients with high blood pressure there has already been damage caused by nitric oxide so this may be why they see more of a beneficial effect from coffee.
Dr Jeremy Pearson, deputy medical director of the British Heart Foundation was sceptical that the benefit was from coffee.
He said: “Living the Greek lifestyle and eating the Greek diet is certainly good for you as long as you don’t smoke the Greek cigarettes.
“However suggesting that your average flustered executive in a British office should drink strong coffee to reduce their blood pressure is nonsense.”
Dr Euan Paul - Executive Director of the British Coffee Association, said: "These new study findings from the University of Athens highlight that moderate coffee consumption is associated with improved elasticity of the arteries amongst those that drink coffee compared with those that drink less coffee.
"This is important as it indicates that coffee consumption may reduce the risk of developing atherosclerosis and future cardiovascular events by improving aortic distensibility.
"Coffee is one of the most heavily researched products in the world today, this study adds to the weight of scientific evidence which shows that moderate coffee consumption of around 4 - 5 cups per day, is safe and may even confer some health benefits."
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