A Calgary researcher is looking for pot smokers, past or present, to participate in a research project at the university.

Cannabis is the most widely used illicit drug in the world and PhD Candidate, Jonathan Stea is trying to determine why most people who smoke marijuana don't develop a dependency.

Stea is looking into the differences between natural and assisted recovery, which is basically why some people can quit on their own and others need help.

He is also examining the physical effects of quitting and says that some people with a dependency suffer physical withdrawal.

"Some of the withdrawal symptoms we are talking about include irritability perhaps some nervousness, anxiety, depressed mood maybe anger, aggression, maybe some physical symptoms such as a stomach ache or nausea," said Stea.

Stea says that research shows that marijuana can cause problems for people and dependency increases dramatically with frequency of use.

The research will help them to understand the recovery process and improve treatment.

It is estimated that one in ten people who use the drug will develop a cannabis dependence disorder eventually.

More than 45 percent of Canadians say they have used marijuana at least once and Alberta and British Colombia have the highest number of users.

For more information on the study visit the University of Calgary website or call the Addictive Behaviors Laboratory at 403-210-9580