Carbonated drinks, coffee increase risk of stroke, study reveals

New research has revealed that frequent consumption of carbonated drinks or fruit juice and drinking more than four cups of coffee per day increases the risk of stroke.

The study reported that fizzy drinks, including both sugar-sweetened and artificially sweetened (diet or zero sugar), were linked to a 22 per cent increased chance of stroke, and the risk increased sharply with two or more of these drinks a day.

The findings came from two analyses of the INTERSTROKE research project, published in the Journal of Stroke and International Journal of Stroke by global research studies, co-led by University of Galway in collaboration with McMaster University, Canada and another international network of stroke researchers.

INTERSTROKE is one of the largest international studies of risk factors for stroke, involving almost 27,000 people, in 27 countries, including almost 13,500 people, who experienced their first stroke.

A stroke is a medical emergency that occurs when the blood supply to part of the brain is cut-off and damages brain cells. It can either be an ischemic stroke, which is usually due to a blood clot or intracerebral haemorrhage, which is bleeding into the brain tissue.

With a focus on people’s consumption of fizzy drinks and fruit juice, the participants of the study came from a broad range of geographical and ethnic backgrounds, with different cardiovascular risk profiles.

The breakdown of the research showed that carbonated drinks and chance of stroke was greatest in Eastern/Central Europe and Middle East, Africa, and South America

The researchers noted that many products marketed as fruit juice were made from concentrates and contained added sugars and preservatives, which might offset the benefits usually linked with fresh fruit, and actually increase stroke risk.

This was linked with a 37 per cent increase in chance of stroke due to bleeding (intracranial haemorrhage) and two of these drinks a day, triples the risks.

Lead researcher and Clinical Epidemiologist, University of Galwayc, Andrew Smyth, said that freshly squeezed fruit juices were most likely to bring benefits, but fruit drinks made from concentrates, with lots of added sugars and preservatives, may be harmful.

“Our research also shows that the chance of stroke increases the more often someone consumes fizzy drinks,” he added.

Smyth encouraged people to avoid or minimise their consumption of carbonated and fruit drinks, and to consider switching to water instead.