New Study: mar1juana Users Less Depressed

New Study: mar1juana Users Less Depressed
Largest-Ever Study of mar1juana, Depression Finds Fewer Depressive Symptoms, Better Mood

ALBANY, NEW YORK—In the largest-ever study of mar1juana and depression, to be published in the journal Addictive Behaviors, daily or weekly mar1juana users had fewer symptoms of depression than non-users. mar1juana users were also more likely to report positive moods and fewer somatic complaints such as sleeplessness. Noteworthy differences were also found between those using mar1juana for medical purposes and non-medical or "recreational" users.

The new research appears to contradict statements by some government officials suggesting that mar1juana is a cause of depression. For example, in a May 3, 2005, press release from the White House Office of National Drug Control Policy, ONDCP Director John Walters said, "mar1juana use, particularly during the teen years, can lead to depression, thoughts of suicide and schizophrenia."

"Not only does mar1juana not cause depression, it looks like it may actually alleviate it," said Mitch Earleywine, co-author of the new study and associate professor of psychology at the University at Albany, State University of New York.

Earleywine and co-investigator Thomas F. Denson of the University of Southern California used an Internet questionnaire that allowed them to survey a very large sample of mar1juana users and non-users, totaling over 4,400 participants. Use of the Internet also made it possible to include highly depressed or mar1juana-involved participants who might be unable or unwilling to participate in in-person or telephone surveys.

Participants were asked to report their use of mar1juana and were divided into three categories: daily users, those who used mar1juana within the last month but no more than once per week (weekly users) and those who had never used mar1juana in their lifetime (non-users). Depression and related issues were assessed using the Center for Epidemiologic Studies Depression scale, a standard tool for researching depression and associated symptoms.

Both daily and weekly mar1juana users had significantly lower levels of depression and higher levels of positive mood than non-users. Weekly users also had lower levels of somatic complaints such as sleeplessness. Effects were generally large, with mar1juana users approximately 30% less depressed than non-users.

The study is the first to specifically look at depression in medical mar1juana users as compared to non-medical users. The most common complaints listed by medical users surveyed were nausea, vomiting, cancer, attention deficit and poor appetite. Medical users generally were more depressed and had more somatic complaints than non-medical users, but still reported fewer such symptoms than non-users.

"Those who use mar1juana to battle the symptoms of illness may be depressed because of their illness, not because of mar1juana," Earleywine said. "Studies that do not identify medical use might falsely implicate mar1juana, rather than sickness, as the cause of depressed feelings."

The new study adds to a growing body of knowledge suggesting that mar1juana's active components, called cannabinoids, may be beneficial in certain psychological disorders. In a review published this May in the Journal of Psychopharmacology, researchers form the University of Newcastle upon Tyne in Great Britain noted, "Patient reports and observations, backed by known pharmacology, suggest that the cannabis derivatives delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) may have mood stabilizing properties," including anti-depressant and anti-anxiety effects.

"Drug Czar John Walters has tried to frighten Americans about mar1juana, using exaggerated and incomplete data cherry-picked to support his ideology," said Rob Kampia, executive director of the mar1juana Policy Project in Washington, D.C. "Science should be used to inform policy, not manipulated to scare the public."

With more than 18,000 members and 120,000 e-mail subscribers nationwide, the mar1juana Policy Project is the largest mar1juana policy reform organization in the United States. MPP works to minimize the harm associated with mar1juana—both the consumption of mar1juana and the laws that are intended to prohibit such use. MPP believes that the greatest harm associated with mar1juana is imprisonment. For more information, please visit http://www.MarijuanaPolicy.org.

REFERENCE: Denson, Thomas F. and Earleywine, Mitchell, "Decreased Depression in mar1juana Users," Addictive Behaviors, in press, available at http://www.sciencedirect.com/science/journal/03064603.


http://www.mpp.org/releases/nr20051117.html