British and Italian researchers have found that eating three bananas cuts the risk of a stroke.

They said that having one banana for breakfast, one for lunch and one in the evening would provide enough potassium to reduce the chances of suffering a blood clot on the brain by around 21 per cent.

The findings suggest that thousands of strokes could be prevented by the consumption of other potassium-rich foods such as spinach, nuts, milk, fish and lentils, reports the Daily Mail.

Although some previous studies have suggested bananas could be important for controlling blood pressure and preventing strokes, results have not always been consistent.

In the latest research, scientists analysed data from eleven different studies - dating back to the mid-Sixties - and pooled the results to get an overall outcome.

They found a daily potassium intake of around 1,600 mg, less than half the UK recommended daily amount for an adult of 3,500mg, were enough to lower stroke risk by more than a fifth.

The average banana contains around 500 milligrams of potassium, which helps to lower blood pressure and controls the balance of fluids in the body.

Too little potassium can lead to an irregular heartbeat, irritability, nausea and diarrhoea.

Researchers from the University of Warwick and the University of Naples said, "Potassium intake in most countries is well below the recommended daily amount."

But if consumers ate more potassium-rich foods and also reduced their salt intake, the annual global death toll from strokes could be cut by more than a million a year.

The study has been published in the Journal of the American College of Cardiology.