Smoking Pot Not a Major Cancer Risk |
Posted by CN Staff on October 26, 2005 at 09:39:43 PT By Amy Norton Source: Reuters New York -- Although both marijuana and tobacco smoke are packed with cancer-causing chemicals, other qualities of marijuana seem to keep it from promoting lung cancer, according to a new report. The difference rests in the often opposing actions of the nicotine in tobacco and the active ingredient, THC, in marijuana, says Dr. Robert Melamede of the University of Colorado in Colorado Springs. He reviewed the scientific evidence supporting this contention in a recent issue of Harm Reduction Journal. Whereas nicotine has several effects that promote lung and other types of cancer, THC acts in ways that counter the cancer-causing chemicals in marijuana smoke, Melamede explained in an interview with Reuters Health. "THC turns down the carcinogenic potential," he said. For example, lab research indicates that nicotine activates a body enzyme that converts certain chemicals in both tobacco and marijuana smoke into cancer-promoting form. In contrast, studies in mice suggest that THC blocks this enzyme activity. Another key difference, Melamede said, is in the immune system effects of tobacco and marijuana. Smoke sends irritants into the respiratory system that trigger an immune-regulated inflammatory response, which involves the generation of potentially cell-damaging substances called free radicals. These particles are believed to contribute to a range of diseases, including cancer. But cannabinoids -- both those found in marijuana and the versions found naturally in the body -- have been shown to dial down this inflammatory response, Melamede explained. Another difference between tobacco and marijuana smoking, he said, has to do with cells that line the respiratory tract. While these cells have receptors that act as docks for nicotine, similar receptors for THC and other cannabinoids have not been found. Nicotine, Melamede said, appears to keep these cells from committing "suicide" when they are genetically damaged, by smoking, for instance. When such cells do not kill themselves off, they are free to progress into tumors. THC, however, does not appear to act this way in the respiratory tract -- though, in the brain, where there are cannabinoid receptors, it may have the beneficial effect of protecting cells from death when they are damaged from an injury or stroke, according to Melamede. All of this, he said, fits in with population studies that have failed to link marijuana smoking with a higher risk of lung cancer -- though there is evidence that pot users have more respiratory problems, such as chronic cough and frequent respiratory infections. If marijuana does not promote lung cancer, that could factor into the ongoing debate over so-called medical marijuana. Melamede said he believes "marijuana has loads of medicinal value," for everything from multiple sclerosis, to the chronic pain of arthritis, to nausea caused by cancer treatment. U.S. government officials, however, maintain that the evidence for medical marijuana is not there. Ten states allow people to use marijuana with a doctor's prescription, but the Supreme Court has ruled that federal law trumps state law. Source: Harm Reduction Journal, October 18, 2005. Source: Reuters Health (Wire) Related Articles & Web Site: Harm Reduction Journal Pot Less of a Cancer Risk Than Tobacco Pot Smoke: Less Carcinogenic Than Tobacco? Home Comment Email Register Recent Comments Help |
Comment #5 posted by FoM on October 26, 2005 at 11:51:42 PT |
I agree with you. I don't mean that smoking isn't harmful but I do believe like you that other invisble fumes we inhale all the time cause damage too. [ Post Comment ] |
Comment #4 posted by lombar on October 26, 2005 at 11:44:13 PT |
When I was young I had a zillion allergies and could not tolerate much. Most of my problems likely originated with being exposed to tobacco smoke as a baby, it gave me asthma that was not developed/diagnosed until I was a teen. That is what I believe now, people then smoked in hospitals, everywhere, ignorance. I had to move out west to escape ragweed, its my nemisis. I do not get sniffles, I choke. Funny thing is that smoke was irritating but perfumes/oils can just incapicate me sometimes. They don't let smokers on the bus but the miasma of mixing perfumes can be far worse to me. There is way more to it than just smoke. Although I will always advocate people quit smoking, I'm not going to assume that smoking is the only cause of premature death. The air we breath, toxins we are exposed to over our lives, dust, dander, radioisotopes, thousands of unnatural chemicals, DNA...etc, are all contributory causes. I was really upset when city council banned smoking indoors but permits a local pulp mill to vent, and the councillors all drive cars. I get really annoyed at people who drive then bitch about smokers as well..The soup we call air is pretty sickening sometimes. A risk/benefit analysis would depend upon highly subjective variables. It is easier to let people do their own. However, some events in life are far more graphic that discussion can convey. A friend of mines mother has been diagnosed with emphysema and will be on oxygen soon. I saw her yesterday. She smoked at least 2 ciggarettes in the 40 mins I was there. She said she would not be able to smoke once on O2 and that after that its only 1-3 years left. Even still she said she will turn off the O2 and have a smoke. There is no doubt what is the cause and she indicated that she is really starting to suffer. A statistic can be ignored, but a funeral cannot. [ Post Comment ] |
Comment #3 posted by FoM on October 26, 2005 at 11:03:23 PT |
Breathing problems have always made me wonder. Many years ago my husband and I quit smoking cigarettes for over 10 years. He has always been wheezy. He was that way as a child and got pneumonia a number of times. The odd thing is all the years that my husband didn't smoke cigarettes he didn't get any improvement in his breathing. I have good lung capacity and the only thing that happened to me during the ten years I didn't smoke was I ate too much food and had a hard time getting my weight back to normal but I finally did. I believe people are predisposed to some things and nothing much will change it for them. Neither of us have or had cancer in our immediate family and most of my family smokes cigarettes and that is taking in a lot of people. [ Post Comment ] |
Comment #2 posted by lombar on October 26, 2005 at 10:51:09 PT |
"though there is evidence that pot users have more respiratory problems, such as chronic cough and frequent respiratory infections." I used to smoke tobacco and cannabis(not together like europeans). I used to get bronchitis 2-3 times per year. After I quit smoking ciggarettes, the only time I ever get bronchitis is directly following a cold, and not every time. Very infrequent even when I was chronic. Smoking anything is probably not good for lungs, it is the ONLY real argument the state has that is even remotely true. Of course 'smoking' is not the only way to ingest cannabinoids! (quoted from Cal NORML/MAPS Study ) "The study suggests that medical marijuana patients can avoid the respiratory hazards of smoking by using a vaporizer. In its 1999 report on medical marijuana, the Institute of Medicine recommended against long-term use of smoked marijuana because of the health risks of smoking. However, the IOM failed to take account of vaporizers." [ Post Comment ] |
Comment #1 posted by cloud7 on October 26, 2005 at 10:30:01 PT |
Did I just see an article titled "Smoking Pot Not a Major Cancer Risk" from a major news organization? I'm shocked. The wall of prohibition is falling. [ Post Comment ] |
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