Writing in the April issue of peer-reviewed journal Vascular Medicine, Gerasimos Siasos and colleagues at the University of Athens Medical School, set out to discover whether drinking the coffee affected the health of elderly residents on the island.
Elderly inhabitants of Ikaria boast the highest rates of longevity in the world, since 1% of the island's isolated, rurally based residents live to be over 90, whereas only 0.1% of Europeans reach this age.
Given that coffee drinking was so widespread worldwide, even small health effects for one type of coffee could impact public health, the researchers write, while stressing the need for more research to document the "exact beneficial mechanisms of coffee in vascular integrity".
Antioxidant-rich Greek coffee
Siasos et al. pay particular attention to links between coffee drinking and endothelial function: the endothelium is a cell layer that lines blood vessels that is affected by aging and habits like smoking.
The scientists focus on coffee due to recent studies suggesting that moderate coffee consumption may slightly cut the risk of coronary heart disease, and positively impact endothelial health.
“The boiled Greek type of coffee, which is rich in polyphenols and antioxidants and contains only a moderate amount of caffeine, seems to gather benefits compared to other coffee beverages,” Siasos et al. write.
Selecting 71 men and 71 women from a group of 673 Ikarian islanders aged 65+, medics collected medical health data and information on lifestyle (including coffee drinking), and tested endothelial function.
87% drank Greek boiled coffee
87%+ of the participants drank boiled Greek coffee daily, and the scientists found that those who drank mainly boiled Greek coffee had a better endothelial function that those drinking other types of coffee.
40% of subjects had a low (<200ml/day) 48% a moderate (200-450ml/day) and 13% a high (>450ml/day) coffee consumption, with an increase in average flow-mediated dilation (or FMD, an evaluation of endothelial function measured by ultrasound) across the consumption levels.
The respective figures were (low) 4.33% ± 2.51%, (moderate) 5.39% ± 3.09% and (high) 6.47 ± 2.72%.
FMD is usually measured in the brachial artery and endothelial function reflects the 'health' of the vessel wall, and is affected by various lifestyle habit (smoking, for instance) and aging.
Siasos et al. evaluated endothelial function in this artery by estimating FMD in this artery, and recording the percentage change in vessel diameter compared to a resting state (baseline brachial artery diameter).
Vascular health connection
Even in subjects with high blood pressure, drinking boiled Greek coffee was associated with improved endothelial function.
“Chronic coffee consumption is associated with improved endothelial function in elderly subjects, providing a new connection between nutrition and vascular health,” the authors conclude.
"This evidence provides a further explanation about how chronic coffee consumption can favorably affect cardiovascular risk, providing a new connection between nutritional habits and cardiovascular health."
Title: ‘Consumption of a boiled Greek type of coffee is associated with improved endothelial function: The Ikaria Study’
Authors: Siasos, G., Oikonomou, E., Chrysohoou, C., Tousoulis, D., Panagiotakos, D., Zaromitidou, M., Zisimos, K., Kokkou, E., Marinos, G., Papavassiliou, A.G., Pitsavos, C., Stefanadis, C.
Source: Vascular Medicine, Vol. 18, No. 2 (April 2013) doi: 10.1177/1358863X13480258