A large glass of wine a day could protect against the most common type of stroke, new research suggests.

The study of 20,000 adults found that up to three units of alcohol a day appeared to reduce the risk of an ischaemic stroke, where the blood supply is stopped due to a blood clot. These account for 85 per cent of all cases.

The research by the Karolinska Institutet and University of Cambridge found that heavier drinking – of any type of alcohol – increased the risks of all types of strokes.