A SLICE of cherry pie a day may do miracles for your health, staving off heart disease, lowering cholesterol and even reducing the risk of diabetes.

And the darker the cherry the better, according t new research, as the health effect comes from the pigment responsible for their red colour.

Sour cherries used in pies, jams and juices are more beneficial than the sweet dessert variety.

Researchers from the University of Michigan in the US reached their results by adding powdered cherries to the food of a group of rats.

After three months, the rats had significantly lower cholesterol levels than another group who had stayed on their normal diet.

The cherry rats also fared better when measured for levels of insulin and other factors linked to metabolic syndrome – a condition which often leads to heart disease or diabetes.

Researcher Dr Steven Bolling said the benefits came from small amounts of cherries, just 1 per cent of the animals' diet.

Unveiling the results at the annual conference of the American Societies for Experimental Biology, he said the team now plans to start trials on humans.

The key to the cherry's success is anthocyanins, natural compounds which help stop cholesterol clogging up arteries. Sour cherries are especially rich in anthocyanins.

Studies have shown that cherries also offer hope for relieving the pain of arthritis and may help us get a good night's sleep by regulating our natural cycle.

The fruit has been used in medicine for hundreds of years. Ground-up cherry stones were used to counteract the pain of chest conditions and stomach problems in the 15th and 16th centuries.

Eating whole cherries was once thought to ward off kidney stones and herbalists brewed the stalks into a tea to treat bronchitis.