A new study suggests red wine polyphenols may protect omega-3 fatty acids from breaking down in the body, offering a possible mechanism for the cardiovascular benefits associated with red wine consumption.
The research, published in Food Research International, investigated the effects of red wine polyphenols on the susceptibility of major fatty acids in human plasma to be oxidised, finding that wine polyphenols significantly protected plasma polyunsaturated fatty acids (PUFA) from peroxidation.
“The results of the present study indicate that red wine polyphenols protect omega-3 PUFA more than omega-6 PUFA of plasma,” said the researchers, led by Roberta Cazzola from University of Milan, Italy.
Cazzola added that their findings may suggest evidence for a mechanism of the anti-inflammatory effects attributed to moderate red wine consumption.
Red wine is a significant natural source of polyphenols in Mediterranean-type diets, with moderate consumption contributing as much as one gram of polyphenols per day to the diet.
Previous research has suggested that consumption of grape products, especially red wine, and other foods rich in polyphenols is associated with decreased risk for cardiovascular disease, cancer and other chronic diseases.
“In particular, moderate red wine consumption (up to 300 mL wine per day) has been shown to be inversely associated with mortality due to cardiovascular diseases,” wrote the researchers.
Cazzola and colleagues noted that although moderate red wine consumption is associated with decreased risk for cardiovascular disease; the underlying mechanisms of such beneficial effects “are not completely understood.”
The new study investigated the effects of red wine polyphenols on the oxidation stability of human plasma fatty acids, in particular those most involved in the inflammatory response such as archidonic acid (AA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). PUFA oxidation was calculated kinetically by measuring their degradation using gas chromatography.
The researchers found that the wine polyphenols increased the resistance to peroxidation of the omega-3 DHA and EPA more than that of the omega-6 AA.
During oxidation, the red wine polyphenols also delayed the increase of the ratio between arachidonate and eicosapentaenoate.
“These results suggest that the association of red wine polyphenols to apolipoproteins makes EPA and DHA less accessible to hydro-soluble radicals than AA, thus providing a biochemical rationale for future ‘in vivo’ studies on the benefits to health of moderate red wine consumption,” concluded the researchers.
Source: Food Research International
Published online ahead of print, doi: 10.1016/j.foodres.2011.07.029
“Red wine polyphenols protect n-3 more than n-6 polyunsaturated fatty acid from lipid peroxidation”
Authors: R. Cazzola, B. Cestaro