Quote:
Originally Posted by WarChild
People who smoke marijuana - even heavy, long-term marijuana users - do not appear to be at increased risk of developing lung cancer. Marijuana smoking also does not appear to increase the risk of head and neck cancers, such as cancer of the tongue, mouth, throat, or esophagus.
These findings were a surprise to the researchers. "We expected that we would find that a history of heavy marijuana use - more than 500-1,000 uses - would increase the risk of cancer from several years to decades after exposure to marijuana," said the senior researcher, Donald Tashkin, M.D., Professor of Medicine at the David Geffen School of Medicine at UCLA in Los Angeles.
The study looked at 611 people in Los Angeles County who developed lung cancer, 601 who developed cancer of the head or neck regions, and 1,040 people without cancer who were matched on age, gender and neighborhood.
http://news.softpedia.com/news/There...er-24575.shtml |
Like I already said, there are many studies, which often contradict each other. Like I also said, the prevailing view is that marijuana is not directly linked to lung cancer.
Here's an abstract of a paper by the same Tashkin whose research the article you linked to was based on:
http://www.ncbi.nlm.nih.gov/pubmed/16128224
Quote:
|
Whereas THC causes modest short-term bronchodilation, regular marijuana smoking produces a number of long-term pulmonary consequences, including chronic cough and sputum, histopathologic evidence of widespread airway inflammation and injury and immunohistochemical evidence of dysregulated growth of respiratory epithelial cells, that may be precursors to lung cancer. The THC in marijuana could contribute to some of these injurious changes through its ability to augment oxidative stress, cause mitochondrial dysfunction, and inhibit apoptosis. On the other hand, physiologic, clinical or epidemiologic evidence that marijuana smoking may lead to chronic obstructive pulmonary disease or respiratory cancer is limited and inconsistent. Habitual use of marijuana is also associated with abnormalities in the structure and function of alveolar macrophages, including impairment in microbial phagocytosis and killing that is associated with defective production of immunostimulatory cytokines and nitric oxide, thereby potentially predisposing to pulmonary infection.
|
And here's a piece linking marijuana use to testicular cancer:
http://www3.interscience.wiley.com/j...TRY=1&SRETRY=0
Or another study linking marijuana use to cancer:
http://www.ncbi.nlm.nih.gov/pubmed/9726006
Basically, at this point in time, there's no consensus on the exact long-term effects of habitual marijuana use. However, studies done so far indicate that smoking marijuana isn't exactly healthy, even if the risks associated with it appear to be fairly limited.
But I'm done with this thread. To anyone without a strong personal interest in the matter, it should be clear that smoking pot in moderation is neither healthy nor extremely unhealthy.