SUGAR-FREE sweeteners could increase glucose intolerance and diabetes risk by affecting bacteria in the gut, a study has suggested.

Widespread use of artificial sweeteners may be fuelling the obesity and diabetes epidemic, it is claimed.

Scientists from the Weizmann Institute in Rehovot, Israel, found that giving mice water laced with three commonly used artificial sweeteners caused them to develop glucose intolerance.

The condition occurs when sugar levels in the blood rise and can lead to Type-2 diabetes.

Tests showed that in mice, sweeteners altered the balance of gut microbes that have been linked to susceptibility to metabolic diseases.

They also affected the composition and function of gut bacteria in a small number of human volunteers, resulting in glucose intolerance after one week.

British experts said the findings were interesting, but urged caution.

Naveed Sattar, professor of metabolic medicine at the University of Glasgow, said: "Current epidemiological data in humans do not support a meaningful link between diet drinks and risk for diabetes, whereas sugar rich beverages do appear to be associated with higher diabetes risk.

"So these findings would not make me choose sugary drinks over diet drinks."