Benefits of Wine Polyphenols on Human Health: A Review

This paper presents  an overview of the health benefits of wine polyphenols, induced by a moderate consumption. Several studies have shown that moderate wine intake may have many beneficial effects on human health and these effects are mainly attributed to the phenolic derivatives, especially flavonoids. Beside flavonoid compounds, phenolic acids (hydroxybenzoic acids and hydroxycinnamic acids) and stilbenes are important non-flavonoid compounds present in grapes and wine. In the present review, the biological role of these classes of polyphenols in wine is briefly introduced, together with the knowledge on their bioavailability. The health-protective properties of wines are mainly due to antioxidant activities and capability to eliminate free radicals of the phenolic compounds. Additionally, these compounds (e.g. catechin and their oligomers and proanthocyanidins, quercetin, resveratrol) have been reported to have multiple biological activities, including cardioprotective, anti-carcinogenic, anti-atherogenic, anti-inflammatory, antiviral and antibacterial properties. Epidemiological and clinical studies have pointed out that regular and moderate red wine consumption (one to two glasses a day) is associated with decreased incidence of cardiovascular disease, hypertension, diabetes, and certain types of cancer, including lung, esophagus, stomach, colon, endometrium, ovarian and prostate cancer. The bioavailability of phenolic compounds differs largely among different polyphenol molecules, thus the most abundant polyphenols in wines are not necessarily those leading to the highest levels of active metabolites in target tissues. Therefore, since wine is a complex mixture, it is likely that a multitude of chemical constituents, as well as their metabolites, act synergistically on human health.