When we think of partying, the first thing that often comes to mind is the clinking of glasses or the popping of a cork. But how much alcohol consumption is considered moderate and how beneficial is moderate drinking for health? According to a Harvard study, moderate drinking is defined as one to two drinks per day for men and one drink per day for women. A “drink” usually means a shot of spirits, a 5-ounce glass of wine or a 12-ounce bottle of beer.

For decades, studies have suggested that moderate drinking can be good for the heart. Observational studies of hundreds of thousands of people have shown that moderate drinkers have lower rates of coronary heart disease and heart attacks compared to nondrinkers and heavy drinkers. This might make sense, since moderate drinking has been linked to increases in “good” cholesterol and a lower likelihood of blood clotting, both of which may contribute to a lower risk of heart attack.

It’s important to note, however, that these results come from observational studies, which, while valuable, cannot conclusively prove cause and effect. There are limitations, such as the possibility that moderate drinkers also engage in other heart-healthy practices that weren’t captured in the studies. Or perhaps nondrinkers have genetic factors that increase their risk of heart disease independent of alcohol consumption.

To truly understand the effects of moderate drinking, randomized controlled trials are needed. Such trials would randomly select people to drink moderately or not drink at all and then carefully monitor their health over a long period of time. Unfortunately, such trials are difficult to conduct, especially over the long periods needed to assess the effects on heart health.

Recent studies have led to some caution, as new evidence does not consistently support the notion that moderate alcohol consumption reduces the risk of heart disease. While this does not necessarily refute previous findings, it does underscore the need for a careful review of all the evidence.

So what’s the current state of affairs? While moderate alcohol consumption may have some heart benefits, it is not recommended solely for that reason. Avoiding alcohol will not harm you, and there is even some evidence that avoiding moderate drinking may slightly increase your risk of diabetes and heart disease. However, excessive drinking, an average of three or more drinks per day, is clearly harmful and carries significant health risks.