Forget apples or mouthwash - a glass of Bordeaux may be the best thing for your teeth.

Scientists have found that certain compounds in red wine could play a role in preventing gum disease and tooth loss. The findings were presented at the annual meeting of the American Association for Dental Research in Orlando, Florida, yesterday.

Researchers from Laval University in Quebec, Canada, studied the effect of extracts from Bordeaux wines on different types of periodontal diseases, which affect the gums and bone around the teeth. Periodontitis affects more than two-thirds of adults over 50 and one in seven people aged between 21 and 50. The diseases can often lead to tooth loss if left untreated.

The scientists looked at polyphenols, compounds that are found in the skin and seeds of grapes. When wine is made from grapes, the alcohol produced by the fermentation process dissolves the polyphenols. White wine does not contain as many polyphenols because the production process involves removing the skins after the grapes have been crushed.

When extracts of Bordeaux wine were used to treat periodontal bacteria in laboratory conditions, the Quebec scientists found that the polyphenols had a "significant inhibitory" effect on the growth of the bacteria. They concluded that the compounds could help to prevent the spread of gum diseases.

However, the experts also found that polyphenols can have a toxic effect on other cells in the mouth, and warned that more work was needed to discover how to harness the benefits from red wine extracts without the risks.

Excess alcohol intake is known to increase the risk of mouth cancer. But red wine has been shown to have a number of health benefits, including reducing the risk of heart disease, cancer and Alzheimer's disease, again because of the polyphenols it contains.

Red wine has also been found to be a good source of fibre, which can help to prevent bowel cancer.

Last month, Italian scientists found that feeding fish a certain polyphenol in red wine, resveratrol, extended their lives by up to 60 per cent.

Scientists are now working on a pill that could deliver the compound in a safer, though obviously less pleasant, way than by drinking red wine.