Consensus and Controversy in the Debate over the Biphasic Impact of Alcohol Consumption on the Cardiovascular System

In the past few decades, research has focused on the importance of addressing modifiable risk factors as a means of lowering the risk of cardiovascular disease (CVD), which represents the worldwide leading cause of death. For quite a long time, it has been considered that ethanol intake has a biphasic impact on the cardiovascular system, mainly depending on the drinking pattern, amount of consumption, and type of alcoholic beverage. Multiple case-control studies and meta-analyses reported the existence of a "U-type" or "J-shaped" relationship between alcohol and CVD, as well as mortality, indicating that low to moderate alcohol consumption decreases the number of adverse cardiovascular events and deaths compared to abstinence, while excessive alcohol use has unquestionably deleterious effects on the circulatory system. However, beginning in the early 2000s, the cardioprotective effects of low doses of alcohol were abnegated by the results of large epidemiological studies. Therefore, this narrative review aims to reiterate the association of alcohol use with cardiac arrhythmias, dilated cardiomyopathy, arterial hypertension, atherosclerotic vascular disease, and type 2 diabetes mellitus, highlighting literature disagreements over the risk and benefits of low to moderate drinking on the cardiovascular system.