Frank Discussion Cannabis Facts for Canadians Oh Cannabis!

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 Claim: Marijuana is unhealthy. It causes lung cancer.

Cannabis and Tobacco Smoke Are Not Equally Carcinogenic
Harm Reduction Journal (UK) - Robert Melamede

Pot Smoking Not Linked to Lung Cancer
Study Shows No Increased Risk for Even the Heaviest Marijuana Smokers

May 23, 2006 - WebMD Medical News
"We know that there are as many or more carcinogens and co-carcinogens in marijuana smoke as in cigarettes," researcher Donald Tashkin, MD, of UCLA’s David Geffen School of Medicine tells WebMD. "But we did not find any evidence for an increase in cancer risk for even heavy marijuana smoking." more...


Although cannabis smoke contains known carcinogens, there have not been any cases of cancer fatalities caused by smoking cannabis.

Kaiser Permanente is a large insurance corporation that has been following the health outcomes thousands of pot smokers for well over a decade. To their surprise, long term cannabis use is not associated with early mortality as is the case with long term cigarette smokers.

Researchers at John Hopkins Medical School also failed to detect any association between cannabis and head, neck and lung cancer.

Unfortunately, any research that concludes cannabis is not a serious threat to health does not get serious covereage in the media.

Kaiser Permanente Study:
"aside from the almost self-evident proposition that smoking anything is probably bad for the lungs, the quarter century since large numbers of Americans began to use marijuana has produced remarkably little laboratory or epidemiological evidence of serious health damage done by the drug."
- Harvard policy analyst Mark Kleiman

John Hopkins Medical School study:
"Marijuana, unlike tobacco and alcohol, does not appear to cause head, neck, or lung cancer, says a researcher from Johns Hopkins Medical School in Baltimore."

Review of Research Concerning Lung Disease and Cannabis:
"There are no epidemiological or aggregate clinical data suggesting that marijuana-only smokers develop lung cancer."

Is cannabis use a risk to health? A look at the evidence
"At present it is estimated that marijuana's LD-50 is around 1:20,000 or 1:40,000. In layman terms this means that in order to induce death a marijuana smoker would have to consume 20,000 to 40,000 times as much marijuana as is contained in one marijuana cigarette. NIDA-supplied marijuana cigarettes weigh approximately .9 grams. A smoker would theoretically have to consume nearly 1,500 pounds of marijuana within about fifteen minutes to induce a lethal response." - DEA Administrative Law Judge Francis L. Young

Pot is not only safe, it also has protective properties... its possible to use pot in a harmful way but the risks are very small compared to alcohol or tobacco use... pot is as safe to use as caffeine which means it can be part of an active healthy lifestyle or a couch potato lifestyle with very little effect on long term outcomes compared to non-users.

- Response submitted by Bob Martin

Heavy Marijuana Smoking Not Linked To Raised Lung, Neck Cancer Risk
May 25, 2006 -

"Researchers from the David Geffen School of Medicine, University of California, were surprised to find there was no link [between marijuana smoking and lung cancer] at all. "

"Smoking of marijuana, be it heavy smoking and/or long-term smoking, is not linked to an increased risk of developing lung and neck cancers, say the researchers. Risk of tongue, mouth, throat and esophagus cancers is not higher either."

(RAND Corporation Provides Objective Research Services and Public Policy Analysis)

Annual Causes of Death in the United States

From the book "Marijuana Myths, Marijuana Facts" by Lynn Zimmer, Ph.D. and John P. Morgan, M.D.:
Myth: Marijuana use has been scientifically proven to be really harmful.
Fact #1: In 1972, after reviewing the scientific evidence, the National Commission on Marijuana and Drug Abuse concluded that while marijuana is not entirely safe, its dangers had been grossly overstated.

Fact #2 In 1995, based on thirty years of scientific research, editors of the British journal Lancet (the British equivalent of New England Journal of Medicine) concluded that "the smoking of cannabis, even long term, is not harmful to health."
Myth: Marijuana is more damaging to the lungs than tobacco.
Fact #1: Moderate smoking of marijuana appears to pose minimal danger to the lungs.

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