Here's a New Reason for Quitting Smoking

Dec. 8, 2010 — -- Cigarette smokers frequently argue that the reason they don't stop smoking is that quitting would make life more depressing. But new research indicates the opposite is true. Persons who quit in a clinical trial actually showed lower signs of depression for weeks and months after giving up the weed.

Smokers who quit were happiest during periods of abstention, and if they began smoking again their moods turned darker, according to psychologist Christopher Kahler of Brown University, lead author of a study in the journal Nicotine & Tobacco Research. Participants in the study who never quit smoking were the most depressed of all. Those who quit entirely were the least depressed at the beginning of the months-long study and they remained the happiest throughout the project.

"We're still puzzling about why that's the case," Kahler said in a telephone interview. "A sense of personal triumph makes a lot of sense. The people in this study were really motivated to succeed. And when you succeed at something that's important to you, you naturally feel better."

But he concedes that many ex-smokers complain that "they felt miserable for weeks" after quitting, and many say they resumed smoking because they felt depressed or anxious or irritated about something in their lives. Yet in this study, the less people smoked, the less they suffered from depression.

Whether Smoking Increases or Decreases Depression Is Debated

The study probes an area that has not been widely studied and the question of whether smoking increases or decreases depression is still a bit up in the air. It's not clear yet whether these findings would apply to everybody, because all the participants were classified as "heavy social drinkers" of alcohol, and 90.7 percent were non-Hispanic whites.

In fact, this wasn't even the initial goal of the study, which was funded by the National Institute of Drug Abuse. Kahler and his colleagues at Brown and the University of Southern California set out to determine if abstaining from alcohol could help people quit smoking.

So they ended up with 236 men and women who volunteered for the study. All of the participants were "heavy drinkers," meaning the men had at least 14 drinks per week and the women had at least seven drinks per week.

Study Revealed Surprising Clues About Depression and Smoking

Abstaining from alcohol had an insignificant effect, Kahler said, in helping participants quit smoking. But the data also contained surprising clues about depression and smoking.

"People say they can't quit because they are going to feel worse psychologically, but we just don't see that," he added.

The participants, averaging 41.5 years of age, really wanted to quit because they enrolled themselves in a rigid clinical program. They were biochemically tested for smoking at 2, 8, 16, and 26 weeks after the date they were supposed to quit.

They were administered a breath test, because smoking leaves carbon monoxide on the breath, and a blood test reveals traces of nicotine, both of which would show if the participant had smoked even a little in the preceding few days.

Ninety-nine of the participants smoked throughout the study, and showed the highest levels of depression, 44 were able to quit for two weeks, 33 abstained for two to eight weeks, 31 quit entirely. The rest were erratic, quitting and resuming at various times.

For Study's Participants, Quitting Led to Happier Outlook on Life

The study noted that "there was significant variability in depressive symptoms based on abstinence (non-smoking) patterns. Those abstinent at all time points (2, 8, 16 and 26 weeks) had particularly low levels of depressive symptoms at baseline, which remained low throughout the follow-up. Smokers who transitioned from smoking to abstinence and back to smoking showed the lowest levels of depressive symptoms when abstinent, while those who were never abstinent showed gradual increases in depressive symptoms over time."

Quitting, at least in this study, clearly led to a happier outlook on life.

"There's no doubt that quitting smoking is a lot of work and requires a lot of persistence to get through some craving and some negative moods, and nicotine withdrawal," Kahler said "That said, those people who succeeded in quitting were less depressed than they were when they started."

It may be hard, he noted, but "being successful feels good enough to overcome" the demons that haunt the person who is trying to stop.

Studies Continue to Demonstrate Importance of Quitting Smoking

The Brown research is only one of several studies released this week showing just how difficult it can be to stop smoking, and just how important it is to do so.

Scientists in Germany revealed that their research shows that smoking actually thins the brain, especially in the cerebral cortex, an area that is responsible for higher-order functions, like language, information processing and memory. Reduced thickness in that region has been associated with impaired cognition and reduced intelligence.

That same area is also associated with impulse control and reward processing, leading the German researchers to conclude that nicotine may trigger the reward system, thus becoming addictive, in the very part of the brain that is thinning.

Meanwhile, researchers at the University of Alabama, Birmingham, reported that exposure to nicotine during pregnancy can affect the newborn, possibly causing such mental disorders as attention-deficit hyperactivity disorder. That research was conducted on rats.

Negative findings like those turn up so frequently that one wonders why anyone smokes, and why anyone even starts.

Brown's Kahler speculates that most people start young and don't realize they may be making a lifelong commitment to tobacco.

"Most people start in adolescence," Kahler said. "So understanding why people smoke means understanding why adolescents make some of the decisions they make. They are focused very much on the short term" and they don't think they will be smokers a few years down the road.

"But some get hooked and addicted," he added. "Nicotine sets up a physical dependence and smoking sets up a psychological dependence."

But New Year's Day is just around the corner. Maybe it's time to dust off that old resolution, and get happy.