According to Time, drinkers, and heavy drinkers (this does not mean drunks), are likely to live longer than those who do not drink, or are drunkards.

But a new paper in the journal Alcoholism: Clinical and Experimental Research suggests that — for reasons that aren’t entirely clear — abstaining from alcohol does tend to increase one’s risk of dying, even when you exclude former problem drinkers. The most shocking part? Abstainers’ mortality rates are higher than those of heavy drinkers. (See pictures of booze under a microscope.)

Moderate drinking, which is defined as one to three drinks per day, is associated with the lowest mortality rates in alcohol studies. Moderate alcohol use (especially when the beverage of choice is red wine) is thought to improve heart health, circulation and sociability, which can be important because people who are isolated don’t have as many family members and friends who can notice and help treat health problems.

But why would abstaining from alcohol lead to a shorter life? It’s true that those who abstain from alcohol tend to be from lower socioeconomic classes, since drinking can be expensive. And people of lower socioeconomic status have more life stressors — job and child-care worries that might not only keep them from the bottle but also cause stress-related illnesses over long periods. (They also don’t get the stress-reducing benefits of a drink or two after work.)

But even after controlling for nearly all imaginable variables — socioeconomic status, level of physical activity, number of close friends, quality of social support and so on — the researchers (a six-member team led by psychologist Charles Holahan of the University of Texas at Austin) found that over a 20-year period, mortality rates were highest for those who were not current drinkers, regardless of whether they used to be alcoholics, second highest for heavy drinkers and lowest for moderate drinkers.