According to government data, up to 90 percent of people addicted to alcohol also smoke. The connection goes the other way too. Smokers are more likely to drink alcohol and have a 2.7 times greater risk of becoming alcohol dependent than non-smokers. While smoking rates overall have steadily declined over the past three decades, the smoking rate among alcoholics has remained persistently high.

Alcohol and nicotine act on common mechanisms in the brain, creating complex interactions. Recent studies show that smoking may actually serve as a neurological cue to have a drink. Researchers think that alcohol fosters feelings of pleasure, which reinforce the effects of nicotine. Similarly, since nicotine stimulates and alcohol sedates the body, the two may moderate each other’s effects.

Studies suggest that the same set of genes that predispose an individual to alcoholism may also predispose them to smoking. And, your genes may put you at higher risk for certain diseases associated with smoking and drinking. In addition, smoking and heavy alcohol use can cause changes to DNA that lead to accelerated biological aging.

The data is clear: drinking makes it harder to quit smoking. But quitting drinking and smoking at the same time is incredibly hard, so it’s generally not recommended by doctors. Seek professional help if you are a committed drinker trying to quit smoking. A doctor or therapist can be a consistent source of accountability and support, and help you pinpoint emotional triggers, find coping strategies and help prevent slip-ups, even if you maintain a modest level of drinking.