DRINKING just one can of diet fizzy drink every day can increase the risk of a heart attack or stroke, research at two medical centres has shown.

The researchers also warn that a couple of daily cans of supposedly "healthier" drinks such as no-calorie lemonade or cola, which have a substantial amount of artificial sweeteners, can raise the risk of liver damage as well as potentially causing diabetes and heart damage.

People who drink diet soft drinks are 43 per cent more likely to have heart attacks, vascular disease or strokes than those who have none, according to the  University of Miami Miller School of Medicine and Columbia University Medical Centre claim.

They found those who drank diet soft drinks every day were 43 per cent more likely to have suffered a 'vascular' or blood vessel event than those who drank none, after allowing for pre-existing vascular conditions such as metabolic syndrome, diabetes and high blood pressure.

A spokeswoman for the researchers said: "Our results suggest a potential association between daily diet soft drink consumption and vascular outcomes. The mechanisms by which soft drinks may affect vascular events are unclear."

She added, however, that more research was needed before significant conclusions could be drawn about the health consequences of soft drink consumption.

Diet soft drinks often contain artificial sweeteners like aspartame, which has been linked to other health problems such as cancer. However to date, heath watchdogs, including the UK's Food Standards Agency, have ruled out any link to ill-health.

The U.S. research team studied the soft drink and diet soft drink consumption of 2,564 people over a 10-year period. The latest study appears in the Journal of General Internal Medicine.

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