Experiments performed with wine samples that had been collected at various time points of the mash fermentation revealed that the increasing content of polyphenols, particularly flavonoids, during this process corresponds to the inhibitory potency on the cellular mechanisms of atherosclerosis. The longer the wine had been macerated with grape solids, the higher were the concentrations of flavonoids, and the more efficiently did the wine interfere with the described molecular events. This is particularly true of growth factor-mediated signals, as red wine dramatically reduced the responsiveness to growth factors and the chemotactic and proliferative potential of vascular cells. When white wine (which does not exert the protective properties) was enriched with flavonoids by incubation with shredded grape seeds, it then also inhibited atherogenic cellular events with the same potency as red wine. Although this experiment further supports the importance of flavonoids as protective substances against atherosclerosis, polyphenol-enriched white wine was not drinkable.

Are the molecular effects of wine polyphenols relevant for the protection from heart attacks
in humans?
Within France, alcohol intake is mostly in the form of red wine. This is particularly true in the south (Toulouse), where the incidence of heart attacks is at its lowest. In contrast, people living in the north (Strasbourg, Lille), who tend to consume less red wine but more white wine, beer and spirits, have a higher risk of myocardial infarction. Based on quantitative analyses of French wines and a reported average wine consumption of 180 ml/day/person in France, the average daily intake of wine flavonoids (catechin, epicatechin, procyanidin dimers B1, B2, B3, and B4) for the French population was estimated as 5 mg/resident/day in white wine drinkers and 32 mg/resident/day in persons that primarily consume red wine. Importantly, flavonoids have been shown to be absorbed after wine consumption in humans.

In fact, the concentrations of flavonoids that were measured in the blood of humans after consumption of two glasses of red wine fully correspond to the concentrations that have been used in research experiments. Consistently, a recent study revealed that flavonoids present in red wine and tea are particularly protective against coronary heart disease, and that an average daily intake of 21 mg corresponds to a 24% decrease of cardiovascular risk. Therefore, the high intake of flavonoids with red wine and other nutritional sources such as fruits, vegetables, tea and chocolate, which also contain small amounts of flavonoids, may at least in part explain the protective effects of the “mediterranean diet” against atherosclerosis. The molecular effects of wine polyphenols, that have been demonstrated by researchers in vascular cells, are likely to provide a molecular explanation for the “French paradox”. Furthermore, the non-alcoholic substances found in red wine could potentially be used for the development of novel pharmacologic strategies against atherosclerotic vascular disease and heart attacks. Nevertheless, wine may taste better than tablets.