About a decade ago, the discovery of the French paradoxthat people living in France have a lower incidence of heart disease than do their British counterparts, despite a comparable intake of dietary fattouched off the ongoing debate over the health benefits of alcohol. Though France is famous for its red wine, scientists soon began examining, and in some cases extolling, the benefits of moderate consumption of any alcohol. Whether or not red wine has unique heart-helping effects was unclear. Research published today in Nature, however, suggests that components specific to red wine provide protection against coronary artery disease.

Roger Corder and colleagues at the Queen Mary University of London first extracted chemicals known as polyphenols from red wine made from Cabernet Sauvignon grapes. The polyphenols, they found, decreased production of the peptide endothelin-1 (ET-1) in cultured animal heart cells by suppressing transcription of the ET-1 gene. Endothelin-1, the authors note, is crucial to the development of atherosclerosis, a disease in which plaques containing cholesterol and lipids clog arteries.

To determine whether this protective property is unique to red wine, the researchers next tested extracts from red, white and ros wines, as well as non-alcoholic red grape juice. For the red wines, the degree to which ET-1 synthesis was inhibited in the cultured cells corresponded to the quantity of polyphenols present, which varies depending on the wine's region of origin and the type of grapes used. Grape juice slowed synthesis of the peptide but was significantly less potent. The white and ros wines, however, displayed no such inhibitory powers. Because the ros wine was also made from Cabernet Sauvignon grapes, the authors suggest that "the active principle in red wine must derive from red-grape skins or other grape components during the vinification process." Just something to keep in mind the next time you're asked "Red or White?"