New research shows that people with mood or anxiety disorders, who are more likely to smoke, see improved symptoms after kicking the habit.

People with mental illnesses—from anxiety to bipolar disorder—are more likely to self-medicate.

When treating a patient for mental illness, experts tend to focus on bad habits that have the most dramatic impact on the patient’s life, namely alcohol and drugs, as they can worsen mental problems. Smoking, however, typically gets a pass.

But new research from the Washington University School of Medicine in St. Louis found that treating nicotine addiction can have positive effects on a person’s mental well-being.

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Researchers analyzed data from 4,800 daily smokers from the National Epidemiologic Study on Alcohol and Related Conditions survey and found that those with addiction problems or psychological issues had fewer problems three years later if they quit smoking.

The first time the survey was given, about 40 percent of daily smokers reported having mood or anxiety issues. Roughly half of daily smokers also had alcohol problems and a quarter had drug issues.

Three years later when the survey was given again, 42 percent of the people who still smoked had mood disorders. Of those who quit, only 29 percent had mood issues. Alcohol and drug use rates were also lower in former smokers.

“We don’t know if their mental health improves first and then they are more motivated to quit smoking or if quitting smoking leads to an improvement in mental health,” lead investigator Patricia A. Cavazos-Rehg said in a statement. “But either way, our findings show a strong link between quitting and a better psychiatric outlook.”

Besides the mental health benefits, there are also the obvious physical health benefits of quitting smoking.

“About half of all smokers die from emphysema, cancer, or other problems related to smoking, so we need to remember that as complicated as it can be to treat mental health issues, smoking cigarettes also causes very serious illnesses that can lead to death,” Cavazos-Rehg said.

Her study was published in the journal Psychological Medicine.

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You would think that someone who smokes cigarettes would admit to being a smoker, but researchers at the University of California, San Diego (UCSD) School of Medicine say that’s not always the case.

In a recent study in Tobacco Control, researchers show that in 2011 nearly 396,000 Californians—or 12.3 percent of the population—regularly smoked cigarettes, yet didn’t call themselves “smokers.” That includes the nearly 22 percent of people who smoked on a daily basis.

Not admitting you are a smoker is a major barrier to quitting. There’s no reason to stop doing something if you don’t do it in the first place, right?

“There is a risk for such smokers to continue to smoke and be adversely impacted by the tobacco they smoke, yet they do not seek any assistance nor do they plan to quit because they falsely believe they are not smokers,” Dr. Wael K. Al-Delaimy, a professor and chief of the Division of Global Health at UCSD said.

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