Are depressed people more prone to addiction -- and why?

Ongoing depression may lead a person to seek comfort in a bottle. See more pictures of mental disorders.
Digital Vision/Getty Images

We all have bad days when we just want to come home, get in comfy pajamas and indulge in guilty pleasures. Maybe a glass or two of red wine, a marathon of sappy movies and an entire carton of ice cream. But what if you felt bad all the time? Are you more likely to become addicted to these things that make you feel better? Will you get to the point where you can't function without that red wine each night, and then will you try more and more drinks and substances in the hope of finding happiness?

Health is largely a story of cause and effect. We know that obesity is likely to lead to diabetes, high cholesterol is a risk factor for heart disease, and high blood pressure is linked to an increased risk of stroke. And while depression has already been linked to several other disorders, such as anxiety, doctors are trying to discern what impact depression might have on addiction.


There's no doubt that there's great comorbidity, or simultaneous occurrence, of addiction and depression. Male addicts have a rate of depression three times higher than the general public, while female addicts have a rate that's four times higher [source: Albrecht, Herrick]. The link between depression and addiction holds true for more traditional substance addictions like nicotine and alcohol as well as more recently recognized impulse-control addictions, such compulsive gambling. Is it any wonder then that Nevada, with the smoky, cocktail-fueled casinos of Las Vegas, ranked as one of the 10 most depressed states in 2007 [source: MHA]?

But which came first -- the addiction or the depression? In one study, about half of patients admitted to a drug treatment program for cocaine claimed pre-existing depression, indicating that rather than seeking out therapists, these people sought out drug dealers [source: Goleman]. In another study, doctors estimated that 10 to 20 percent of alcoholics begin drinking to feel better because of depression [source: Schmeck]. Self-medicating depression may also be a factor in Internet addiction as well [sources: Phillips; Young, Rogers].

­Other studies, however, seem to find that the addiction precedes the depression. For example, one study considering risky behaviors in adolescents found that taking drugs and engaging in sex at a young age predicted an increased likelihood of depression, but depression in the youngsters wasn't a good indicator of whether they would turn to drugs or sex [source: Hallfors et al.].

Is it a ­chicken-and-egg scenario? Possibly. But before we decide, let's peer through the smoky air and consider nicotine use. So far, this addiction provides some interesting clues about the interplay between depression and addiction. Turn the page to see if smoking is a way for the depressed to puff themselves up.


Do We Self-Medicate Depression, or Is There Another Explanation?

A cigarette can give you a lift, but at what cost?
altrendo images/Altrendo/Getty Images

Several studies have shown that major depression is more than twice as common in smokers as nonsmokers [source: Mansnerus]. And if one guy is always standing outside smoking, you might want to ask him if he needs to talk -- these studies also indicate that depression is much more likely when a person feels the need to light up a cigarette continuously [source: Mansnerus].

But is a smoker depressed because of the clinging smell of smoke and their yellow teeth? Or are these the unfortunate side effects of the one thing that makes a depressed person happy? Scientists hypothesize that any addiction may be an attempt to self-medicate the depression -- witness a person who drinks to numb pain and drown out negative thoughts -- but the evidence seems particularly compelling in the case of cigarettes. Depression is tied to imbalances of certain chemicals in the brain, most notably the neurotransmitters serotonin and dopamine. Each puff of nicotine stimulates the release of those very neurotransmitters. Even in nonsmokers, a nicotine patch was found to decrease the symptoms of depression [source: Duke University Medical Center].


But not every depressed person turns to cigarettes; some hit the corner bar nightly to fix their brain chemistry. Alcoholism has been linked to a deficiency in serotonin levels in the brain, which can cause depression but also hinder a person's ability to rein in impulses [source: Goleman]. This means that alcoholics may continue to hit the bottle even though they know it's not a long-term solution, but also as a form of self-medication for other areas of life. If these people lack impulse control when it comes to anger, for example, they may turn to more alcohol to feel relaxed and refrain from outbursts.

However, one reason why it's hard to know whether the addiction leads to depression is because of the role of dopamine in addiction. Dopamine is associated with the brain's pleasure and reward center, and while depressed people may lack it, the brain scans of many addicts show that they actually have high levels of dopamine [source: Phillips]. This seems to suggest that addicts' brains start off on a pleasure high that they have to keep feeding, rather than a deficit that they try to address through addiction.

So while comorbidity of addiction and depression is common, it's probably too easy to say that one leads to another. There are a host of other factors involved, including genetics, environment and income level. Gender may also play an important role; it seems that men are more likely to develop the addiction before the depression, whereas women typically experience depression first [source: Albrecht, Herrick].

It's important to remember that even if depression made a person prone to addiction, curing just the depression won't necessarily put an end to the addiction. Once a person is addicted, he or she has two problems to deal with and should consider treatment programs that focus on both issues. Depression may also be a factor in whether someone is able to successfully quit an addiction, especially because quitting a substance or behavior may exacerbate the feelings of sadness.

For more information on depression and addiction, please see the links on the next page.


Lots More Information

Related HowStuffWorks Articles

More Great Links

  • ­Albrecht, Ava T. and Charles Herrick. "100 Questions and Answers about Depression." Jones and Bartlett Publishers. 2005.
  • Brody, Jane E. "Helping the depression-prone to quit smoking." New York Times. Aug. 31, 1994. (Oct. 21, 2008),%20prone%20to%20addiction&st=cse
  • "Cocaine Use Tied to Loss of Pleasure Sense." New York Times. Jan. 7, 2003. (Oct. 21, 2008),%20prone%20to%20addiction&st=cse
  • Duke University Medical Center. "Nicotine Lessens Symptoms of Depression in Nonsmokers." ScienceDaily. Sept. 13, 2006. (Oct. 21, 2008)
  • Goleman, Daniel. "Scientists Pinpoint Brain Irregularities in Drug Addicts." New York Times. June 26, 1990. (Oct. 21, 2008)
  • Hallfors, Denise D., Martha W. Waller, Daniel Bauer, Carol A. Ford and Carolyn T. Halpern. "Which Comes First in Adolescence--Sex and Drugs or Depression?" American Journal of Preventative Medicine. 2005. (Oct. 21, 2008)
  • Mansnerus, Laura. "Smoking. Is It a Habit or Is It Genetic?" New York Times. Oct. 4, 1992. (Oct. 21, 2008)
  • Mental Health America. "Ranking America's Mental Health: An Analysis of Depression Across the States." Dec. 14, 2007. (Oct. 21, 2008)
  • Phillips, Helen. "Hooked: Why your brain is primed for addiction." New Scientist. Aug. 26, 2006. (Oct. 21, 2008)
  • Saint Louis University. "It's In Their Genes: Study of Twins Connects Smoking Addiction with Major Depression." ScienceDaily. July 17, 2007. (Oct. 21, 2008) /releases/2007/07/070716132424.htm
  • ­­Schmeck, Harold M. Jr. "Depression and Anxiety Seen as Cause of Much Addiction." New York Times. Nov. 15, 1988. (Oct. 21, 2008)
  • Young, Kimberly S. and Robert C. Rodgers. "The Relationship Between Depression and Internet Addiction." CyberPsychology and Behavior. 1998. (Oct. 21, 2008)