The health effects of alcohol have been studied for decades. While it is clear that excessive alcohol consumption is harmful, hundreds of studies have demonstrated that light to moderate alcohol consumption may reduce the risk of certain cardiovascular conditions. Light to moderate alcohol consumption has been consistently associated with lower risk of coronary heart disease (CHD) among a wide variety of population groups including men and women, those with hypertension, diabetes and heart disease. Alcohol has been associated with increases in HDL cholesterol and lower risks of diabetes. It is felt that this is one important mechanism by which alcohol could lower the risk of heart disease.
A key issue to understanding the complex relationships of alcohol intake is the shape of the relationship. For example, the shape of the associations appears to be bimodal with lower risk at light to moderate levels of consumption and higher risk at heavy levels of consumption. This strongly suggests that mechanisms for benefit and harm may be distinct. These types of relationships are unusual in epidemiology and make recommendations challenging.
Cardiovascular disease is only one component of total mortality. Alcohol has other health effects. For example heavy alcohol has been shown to increase the risk of certain cancers and can cause cardiomyopathy. This makes the overall relationship of alcohol intake on total mortality complicated. Recent meta-analyses suggest that careful attention to the subpopulation may need to be taken when considering specific alcohol recommendations. In this presentation, the factors that go into the complex relationship of alcohol and other conditions will be carefully explored.