Drinking a can of diet soft drink a day associated with almost three times higher risk, say researchers – but critics warn against causal connection.
Sales of diet versions of soft drinks have boomed in recent years, with full-sugar drinks now retaining just 38% of the market.
Consuming a can a day of low- or no-sugar soft drink is associated with a much higher risk of having a stroke or developing dementia, researchers claim.
Their findings have prompted renewed questions about whether drinks flavoured with artificial sweeteners can increase the risk of serious illness, as heavily sugared drinks have already been shown to do.
“Drinking at least one artificially sweetened beverage daily was associated with almost three times the risk of developing stroke or dementia compared to those who drank artificially sweetened beverages less than once a week,” according to the American researchers who carried out a study published in Stroke, the journal of the American Heart Association.
“After adjustments for age, sex, education (for analysis of dementia), calorific intake, diet quality, physical activity and smoking, higher recent and higher cumulative intake of artificially sweetened soft drinks were associated with an increased risk of ischaemic stroke, all-cause dementia and Alzheimer’s disease dementia,” the co-authors write.
Ischaemic strokes occur when blood cannot get to the brain because of a blockage, often one caused by a blood clot forming in either an artery leading to the brain or inside a vein in the brain itself. They comprise the large majority of the 152,0000 strokes a year which occur.
“To our knowledge, our study is the first to report an association between daily intake of artificially sweetened soft drink and increased risk of both all-cause dementia and dementia because of Alzheimer’s disease,” the co-authors added.
However, they admitted that they could not prove a causal link between intake of diet drinks and development of either medical condition because their study was merely observational and based on details people provided in questionnaires logging their food and drink habits.