Scientists have moved one step closer to understanding the 'French Paradox'. A recent study carried out in France claims to have found differences in the 'good cholesterol' of red wine drinkers which could account for the drink's beneficial effects against cardiovascular disease.
Researchers at the French medical research institute Inserm analysed the high-density lipoprotein composition of teetotallers, regular drinkers and heavy drinkers (most of whom generally drank red wine). They found that HDL cholesterol increased as alcohol consumption increased, and that HDL particles from wine consumers were richer in certain components that can play a protective role in cardiovascular disease.
The well-documented relationship between moderate consumption of alcohol - particularly red wine - and reduced risk for heart attack may be partly explained by alcohol's relationship to increased levels of HDL. The new research provides an in-depth look at that connection.
"This study provides, for the first time, a detailed characterisation of HDL composition in regular drinkers," wrote lead author Bertrand Perret.
Forty-six men aged between ages 35 and 65 participated in the study. Their dietary patterns, including alcohol intake, were examined through a process in which a dietician helped participants recall their food consumption over the previous three days.
The men also completed an extensive questionnaire on their drinking habits. They were categorised into three groups on the basis of their self-reported alcohol consumption: teetotallers, regular drinkers (who drank less than 35 grams of alcohol each day), and heavy drinkers (who drank 35 to 60 grams of alcohol each day).
After participants fasted overnight, their blood samples were analysed for HDL and other components related to cardiovascular disease. Researchers analysed the nutrition data and collected information on smoking and medical history, including current blood pressure and physical activity, to mitigate the possibility that other factors caused the HDL differences in the three groups.
"Our study shows that the increase in HDL levels observed in regular drinkers is associated with an enrichment of HDL particles in polyunsaturated phospholipids, and particularly in those containing omega-3 fatty acids, an effect that might be, in itself, beneficial against cardiovascular diseases," said Perret.
Perret is calling for further research to test the possible mechanisms underlying the differences in HDL fatty acid composition observed in this study.
Full findings are published in the August issue of Alcoholism: Clinical and Experimental Research.