THE ads were right - Guinness is good for you - but Eurocrats have warned that no such claims will be entertained.
One pint of Guinness a day can reduce the risk of blood clots that cause heart attacks, according to new research presented at the annual meeting of the American Heart Association in Orlando, Florida.
But new EU legislation will ban advertisements which promote alcohol as beneficial to health out of concern that alcohol can be abused.
However, scientists investigating the health benefits of drinking beer found that stouts like Guinness worked much better than lager.
They said dark beers were packed with anti-oxidant compounds called flavonoids which help reduce damage to the lining of the arteries.
Researchers at the University of Wisconsin carried out laboratory tests comparing the health benefits of Guinness with Heineken.
They fed beer to dogs with clogged arteries, then measured the effects on the stickiness of blood-clotting cells. The results showed only those dogs fed Guinness had reduced clotting activity making them less likely to have a heart attack.
Flavonoids help prevent the oxidation of cholesterol, which contributes to hardening of the arteries which can eventually lead to life-threatening clots.
They also help arteries to dilate, which improves blood flow and blood pressure, said Professor John Folts who led the study.
He is also carrying out similar tests on humans and said for maximum benefit a person would need to drink just over one pint of Guinness a day.
But alcohol products are not allowed to carry claims of health benefits under forthcoming EU legislation, said Beate Gminde, spokesperson for EU Commissioner for Health and Consumer Protection David Byrne.
While foods such as yogurts that can prove health benefits are allowed to proclaim this fact on their labels, this was specifically banned for drinks containing more than 1.2pc alcohol.
"Even if it's true that it has a health benefit, alcohol is something that can be abused," she said. The new EU ban on unproven health claims is due to come into effect in 2005.
Flavonoids are also found in dark fruits and vegetables, red wine and chocolate.