ATLANTA, Ga. (CBS Atlanta) – According to a new study, heavy smoking of marijuana may double the risk of contracting lung cancer.
Researchers studied nearly 49,000 Swedish men. The men were surveyed about their lifestyle in 1969-1970. Researchers found that those classified as “heavy” pot users when they were young were more than twice as likely to have lung cancer by 2009.
“It is seen as organic and natural,” Russ Callaghan, a psychiatry professor at the University of Northern British Columbia and lead author in the study told the National Post.
Other leading researchers in the file find this study contradicting and suspect.
“Though marijuana smoke does contain cancer-causing chemicals, the majority of people simply don’t consume enough of it to get ill,” Hal Morgenstern, a University of Michigan epidemiologist and a member of the International Lung Cancer Consortium, the group that dismisses the cancer connection, told the paper.
Researchers admitted that they were not able to trace how much the participants used marijuana.
Morgenstern went on to say that it is possible that those who were heavy pot smokers when young could have switched to cigarettes when older so it is possible that tobacco, not marijuana, made them sick.
The study was published in the journal Cancer Causes and Control.