Research on alcohol consumption is in a pickle. There’s no question that pounding one drink after another is bad for your health. Things get murkier when it comes to “moderate” drinking. What does that mean? What’s the limit? Can a health-conscious person serenely order a second round?

The alcohol industry has long embraced the notion that alcohol in moderation not only won’t harm you but is actually good for you. The hypothesis gained traction in the early 1990s when “60 Minutes” reported on what is called the French Paradox. The French have low rates of heart disease despite all the butter, cream, foie gras, etc. in the Gallic diet. Some researchers suggested that compounds in red wine, also favored by the French, explain the paradox.

Many studies have shown that people who drink any kind of alcohol in moderation — wine, beer, spirits — have lower rates of heart disease than people who abstain or who drink heavily. But the evidence is stubbornly ambiguous.