A can of diet fizzy drink a day could cause a stroke or heart attack, warn scientists.
With obesity rates rising, artificially sweetened soft drinks are marketed as healthier alternatives to full-fat beverages, due to their lack of calories.
But U.S. researchers have found that those who drank diet soft drinks daily were 43 per cent more likely to suffer a vascular event, hardening of the arteries leading to heart attack or stroke, than those who drank none.
The study by the University of Miami Miller School of Medicine and at Columbia University Medical Center, looked at data from 2,564 participants in the Northern Manhattan Study, which was designed to determine stroke incidence, risk factors and prognosis in a multi-ethnic urban population.
The researchers looked at how often individuals drank soft drinks - diet and regular - and the number of vascular events that occurred over a ten-year period.
While those who drank diet fizzy drinks daily were more at risk of heart attack and stroke, they found that regular soft drink consumption and a more moderate intake of diet soft drinks do not appear to be linked to a higher risk of vascular events.
Researcher Hannah Gardener and colleagues, whose findings appear online in the Journal of General Internal Medicine, examined the relationship between both diet and regular soft drink consumption and risk of stroke, myocardial infarction (or heart attack), and vascular death.
"Our results suggest a potential association between daily diet soft drink consumption and vascular outcomes,” said Gardener.
“However, the mechanisms by which soft drinks may affect vascular events are unclear.
There is a need for further research before any conclusions can be drawn regarding the potential health consequences of diet soft drink consumption.”