In general, moderate drinking - a drink or two per day - is considered a potentially heart-healthy habit. A number of studies have found that moderate drinkers have lower risks of heart disease than teetotalers do.
Research suggests that alcohol can increase "good" HDL cholesterol, has anti-inflammatory effects in the blood vessels and may make the blood less prone to clotting.
On the other hand, regular heavy drinking may increase blood pressure, promote blood clotting and contribute to development of arrhythmias.
References:
Occasional binges may undo alcohol's heart benefits. Reuters, 2010.
Monounsaturated fats found in vegetable oils, nuts and avocados increase "good" HDL cholesterol levels by 12% http://goo.gl/GBQa5
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