Wine, polyphenols and Mediterranean diet. What else is there to say?
Grupo de Investigación en Polifenoles (GIP-USAL), Universidad de Salamanca, Spain
A lot of literature has been published claiming the cardiovascular benefits of moderate (red) wine drinking, which has been considered a distinguishing trait of the Mediterranean diet. Indeed, red wine contains relevant amounts of polyphenols, especially flavonoids, for which evidences on their biological activity and beneficial health effects are abundant. Ethanol itself may exert positive actions on the cardiovascular system by increasing HDL-cholesterol and preventing platelet aggregation. However, it is also well known that alcohol has severe consequences for health. Among others, it is directly related to a number of non-communicable diseases, like liver cirrhosis or diverse types of cancer. The IARC classifies alcohol as a Group 1 carcinogen, causally associated with the development of cancers of the upper digestive tract and liver, and with sufficient evidence to be positively associated with colorectum and female breast cancer. Furthermore, the associations between wine consumption and cardiovascular health mostly rely on observational studies, but hardly direct studies exist to actually prove a causal relationship in humans. In these circumstances, it is tricky, if not irresponsible, to spread any message on the benefits of moderate wine drinking, about which no actual consensus exists. It should be further considered that another hallmark of the Mediterranean diet is the richness in fruits, grains and vegetables that are also good sources of flavonoids and other phytochemicals and lack the risks of wine. All these aspects will be carefully examined in this lecture.