Women who have just one cola or soft drink a day increase their risk of a stroke by 83 per cent. All fizzy soft drinks seem to have a similar effect, whether diet, sweetened or low-calorie.
The drinks affect women far more than men, whose risk of stroke increases only slightly, even if they also drank one fizzy drink every day.
The effect seems to happen over a long period of time. Researchers from Osaka University in Japan made the discovery after they tracked the lifestyles and diets of 40,000 men and women for 18 years.
Around 2,000 of the participants suffered a stroke during the study, and the researchers discovered that the drinks may have been responsible for the women's strokes. Compared to women who never drank fizzy drinks, those who drank just one a day had an increased risk of an ischemic stroke-where there is a haemorrhage in the brain-by 83 per cent. Men were only marginally affected.
Am J Clin Nutr, 2012; doi: 10.3945/ajcn.112.037903