BBC News LinkThe old advertising slogan "Guinness is Good for You" may be true after all, according to researchers.
A pint of the black stuff a day may work as well as an aspirin to prevent heart clots that raise the risk of heart attacks.
Drinking lager does not yield the same benefits, experts from Wisconsin University told a conference in the US.
The Wisconsin team tested the health-giving properties of stout against lager by giving it to dogs who had narrowed arteries similar to those in heart disease.
They found that those given the Guinness had reduced clotting activity in their blood, but not those given lager.
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