New research has found that heavy drinkers who are trying to stop smoking may find that reducing their alcohol use can also help them quit their daily smoking habit. Heavy drinkers’ nicotine metabolite ratio — a biomarker that indicates how quickly a person’s body metabolizes nicotine — reduced as they cut back on their drinking.

Past research has suggested that people with higher nicotine metabolism ratios are likely to smoke more and that people with higher rates have a harder time quitting. Slowing a person’s nicotine metabolism rate through reduced drinking could provide an edge when trying to stop smoking, which is known to be a difficult task, said Sarah Dermody, an assistant professor at Oregon State University and the study’s lead author.

“It takes a lot of determination to quit smoking, often several attempts,” Dermody said. “This research suggests that drinking is changing the nicotine metabolism as indexed by the nicotine metabolite ratio, and that daily smoking and heavy drinking may best be treated together.”

The study was just published in the journal Nicotine & Tobacco Research.

Dermody, who is based in in the School of Psychological Science in OSU’s College of Liberal Arts, studies risky behaviors such as alcohol and nicotine use with the goal of better understanding factors that contribute to alcohol and nicotine use and how best to intervene with problematic use of these substances.

Use of both alcohol and cigarettes is widespread, with nearly 1 in 5 adults using both. Cigarette use is especially prevalent in heavy drinkers. Drinking is a well-established risk factor for smoking, and smoking is well-established risk factor for drinking.

Dermody and colleagues at the Centre for Addiction and Mental Health in Toronto, Canada, wanted to better understand the links between the two. They studied the nicotine metabolite ratio, an index of nicotine metabolism, in a group of 22 daily smokers who were seeking treatment for alcohol use disorder — the medical term for severe problem drinking — over several weeks.

Read more at Oregon State University