People who "drink heavily every so often" are 45% more likely to develop coronary heart disease

Occasional heavy drinking was defined as having 5 or more standard drinks in a day at least 12 times per year. "Regular" heavy drinkers - those who averaged at least 5 drinks per day, were excluded from the analysis.

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
Alcohol literally kills: Gary Moore had 380mg/dL in his blood, Winehouse 416mg/dL when she died surrounded by 3 empty vodka bottles. Telegraph UK, 2012. 

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