Those seeking a longevity-boosting tipple should turn their attention to red wines from Sardinia and south-west France, a study concludes.
Procyanidin levels depend on how the wine is made
UK researchers discovered chemicals called procyanidins were responsible for red wine's well-documented heart-protecting effect.
And they found traditionally made wines from these areas had more procyanidins than wines in other parts of the world.
The research is published in the journal Nature.
Previous studies have revealed regular, moderate consumption of red wine is linked to a reduced risk of heart disease and lower mortality.
A class of chemicals called polyphenols, of which there are many varieties, are thought to be responsible.
Using endothelial cells (cells that line the vascular system), the researchers pinpointed polyphenols called procyanidins as those that provided the most potent protective effect.
They then tested red wines from around the world to measure their levels of procyanidins, including wines from Nuoro province in Sardinia and the Gers region of the Midi-Pyrenees in south-west France, areas famous for their population's longevity.
They discovered wines from these regions had on average between two and four times the level of procyanidin compared with wines from countries including Spain, Australia, South America and the US.
Professor Roger Corder, from the William Harvey Research Institute, at Queen Mary, University of London, said: "There is a 19th Century expression: 'A man is only as old as his arteries', which can be taken to mean that those with the healthiest arteries live longer.
"So it was of great interest to us when we found both in Sardinia and in south-west France that the wines made in these in areas had higher levels of procyanidins."
The researchers believe the way that wines are made is the key.
In traditional wine making, said Professor Corder, grapes have a three to four week fermentation period, allowing for full extraction of the chemical from the skin and the seed.
Modern-style wines are only fermented for a week, resulting in little or no procyanidin.
He added that the grape was also important and the tannat, cabernet sauvignon and Nebbiolo grapes made procyanidin-rich wines.
Professor Corder said: "The traditional production methods used in Sardinia and south-western France ensure that the beneficial compounds, procyanidins, are efficiently extracted.
"This may explain the strong association between consumption of traditional tannic wines with overall wellbeing, reflected in greater longevity."
Cathy Ross, cardiac nurse at the British Heart Foundation (BHF), said: "While we have known for some time that a moderate amount of alcohol can help to reduce your risk of developing heart disease, we would not recommend anyone to start drinking. Those who do enjoy a tipple should keep within the recommended levels.
"There are better ways to reduce your risk. Stopping smoking, eating a healthy diet low in saturated fat and getting at least 30mins of exercise five times a week will all help your heart."