Frequent drinking of fizzy drinks or fruit juice is associated with an increased risk of stroke, according to new findings from global research studies co-led by University of Galway, in collaboration with McMaster University Canada and an international network of stroke researchers. The research also found that drinking more than four cups of coffee per day also increases the risk of stroke. The findings come from two analyses of the INTERSTROKE research project which have been published—the effects of fizzy drinks, fruit juice/drink and water was reported in the Journal of Stroke , and the findings related to tea and coffee were published in the International Journal of Stroke .

Stroke occurs when the blood supply to part of the brain is cut-off and damages brain cells—it can either be ischemic stroke , which is usually due to a blood clot, or when there intracerebral hemorrhage, which is bleeding into the brain tissue. 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. Those who took part in the study came from a broad range of geographical and ethnic backgrounds, with different cardiovascular risk profiles, including Ireland and the UK.

The study which focused on people's consumption of fizzy drinks and fruit juice found: Lead researcher on both studies, Professor Andrew Smyth, Professor of Clinical Epidemiology at Univer.