Red Wine Consumption and the Impact on Cardiovascular Health: The Methodological Barriers of Observational Study Design.

Cardiovascular disease (CVD) is the leading cause of death among communicable and noncommunicable diseases, and its prevalence is going to rise even more by 2030. The discovery of different "functional" foods containing a plethora of bioactive compounds is considered an ally in the effort to reduce the global CVD burden in the context of primary prevention. It has been about 3 decades since the observation that red wine consumption in French population could lead to lower coronary heart disease risk despite the high dietary consumption of saturated fats, known as the "French paradox." Since then, numerous epidemiological studies, mainly observational, have emerged in order to investigate this association with great enthusiasm. However, due to the nature of these studies, the scientific community has raised concerns about the methodological approach of the studies and thus the generalization of their results. Therefore, the current review aims to summarize some of the major methodological issues deriving from observational studies on the association between red wine consumption and cardiovascular health and to highlight the importance of higher quality study design in the general effort of drawing safer conclusions on this topic.