One large glass of wine a day could contain enough of a tumour-fighting compound to prevent bowel cancer, research suggests.
The plant chemical, resveratrol, is found in the skins of grapes and concentrated in red wine.
Scientists have long known that resveratrol has anti-cancer properties, as well as effects that might benefit diabetes and heart disease patients.
But a question mark remains over what dose of the compound it is best to take.
The new research suggests that for fighting bowel cancer it is very small - around five milligrams per day.
That is about the amount of resveratrol typically found in one large glass of red wine, or two small glasses.