NEW YORK (NYT) - It may be the most palatable advice you will ever get from a doctor: Have a glass of wine, a beer or a cocktail every day, and you just might prevent a heart attack and live longer.

But the mantra that moderate drinking is good for the heart has never been put to a rigorous scientific test, and new research has linked even modest alcohol consumption to increases in breast cancer and changes in the brain.

The National Institutes of Health in the US is now starting a US$100 million (S$138 million) clinical trial to test for the first time whether a drink a day really does prevent heart attacks.

And guess who is picking up most of the tab?

Five companies that are among the world's largest alcoholic beverage manufacturers - Anheuser-Busch InBev, Heineken, Diageo, Pernod Ricard and Carlsberg - have so far pledged US$67.7 million to a foundation that raises money for the National Institutes of Health.

The effort to study the benefits and risks of alcohol will recruit nearly 8,000 volunteers aged 50 or older at 16 sites around the world.

The trial will follow them for six years to see which group - the moderate drinkers or the abstainers - has more heart attacks, strokes and deaths.