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Pot vs. Tobacco: Which Is The True Cancer Risk?

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As the reality of legalized non-medical marijuana looms large, Canadians want to know if it's as dangerous as cigarettes.

Or is pot actually "infinitely worse," as former Prime Minister Stephen Harper famously declared during the recent federal election?

It's neither, science now asserts. In fact, Harper couldn't have been more wrong - at least in terms of pot's purported threat as a deadly carcinogen. So suggests the U.S. government's National Cancer Institute (NCI), which even claims that cannabis can actually combat the risk of cancer.

The NCI's findings represent a stunning about-face by the U.S. government, which insisted for decades that cannabis has no medicinal value. Yet the feds finally admitted a few weeks ago that "cannabis has been shown to kill cancer cells in the laboratory" in the latest update of the NCI's web site.

Animal studies were cited as proof that cannabinoids can destroy cancer cells, while still protecting normal cells. The results of the NCI's research echo several other studies conducted in the U.S. in recent years. (More on this in a moment.)

None of this comes as a surprise to Neil Belot, who until recently served as the Executive Director of Canada's national trade association for licensed producers, known as the Canadian Medical Cannabis Industry Association.

In spite of such positive news, there's still plenty of misinformation surrounding this historically stigmatized plant, Belot says. In fact, the scarcity of information in medical school textbooks about the factual health benefits of cannabinoids continues to contribute to the confusion, he adds.

He's now calling on Canadian medical schools to help the healthcare practitioners of tomorrow gain a fuller appreciation of the human endocannabinoid system. Which is involved in many important physiological processes, such as immune function, inflammation, appetite, pain, wake/sleep cycles, and the regulation of stress.

Belot is now a senior executive with a publicly-listed licensed producer -- Aurora Cannabis (CSE: ACB). His company is one of the largest of only 27 federal-government-approved growers/distributors of pharmaceutical-grade cannabis for medical patients in Canada.

"Companies like Aurora provide cancer patients and people with other illnesses with a safe, quality-controlled medicinal product that has been shown to have a wide range of therapeutic benefits and in some cases may actually fight cancer, rather than cause it," he says.

"So it's frustrating to hear political rhetoric that suggests cannabis is more harmful than tobacco. This is unequivocally untrue. Unfortunately, this misinformation plays on the fears, stigma, and vulnerabilities of so many people who stand to benefit from medical marijuana."

He adds, "To mitigate some of these fears, Aurora has entered an agreement for Canadian distribution rights for a new device called the Mystabis -- a pressurized inhaler that uses similar technology to an asthma puffer, and does not use heat or combustion to deliver its precise controlled doses of cannabinoids."

Belot also points to the NCI's findings, as well as other research, as proof of marijuana's anti-cancer properties. They include a 2009 study conducted at New England's Brown University. It revealed an increased risk of head and neck tumours for cigarette smokers and drinkers, while "moderate marijuana use is associated with reduced risk".

Even long-term cannabis use doesn't seem to be harmful. So suggests another federally-funded U.S. study involving 5,115 participants who were assessed over a 20-year period. Investigators at the University of California at San Francisco announced their conclusions in the Journal of the American Medical Association three years ago.

Neither should heavy cannabis smokers worry about developing lung cancer, according to researchers at the University of California at Los Angeles. In a study published as far back as 2006, lead researcher Dr. Donald Tashkin described his findings "against our expectations" that there'd be a link to cancer. "What we found instead was no association at all, and even a suggestion of some protective effect."

Conversely, the same study found that two-pack-a-day cigarette smokers were found to have nearly a 2,000% increase in lung cancer risk. It's also worth noting that tobacco smoke contains up to 4,000 chemicals, the vast majority of which are carcinogens, according to the Canadian Cancer Society.

And among the leading causes of death in Canada -- cancer, heart disease, and stroke -- cigarette smoking is a considerable risk factor, the society also says. It accounts for about 37,000 deaths per year, statistics show.

In terms of medical treatment, tobacco use also costs Canada's health care system an estimated $4.4 billion per year. In comparison, studies of cannabis use have not shown any increased susceptibility to physical illness or premature death.

However, even if pot isn't a dangerous carcinogen - unlike tobacco - it still doesn't come completely risk-free. So says Dr. Steven Laviolette from Western University's Schulich School of Medicine & Dentistry; he researches the effects of nicotine and marijuana on the brain.

At worst, habitual marijuana use has been linked to an increased risk of schizophrenia in early adulthood, he cautions. And at the least, it irritates a person's airways, causing unpleasant phlegm production and associated bouts of coughing.

Dr. Laviolette also agrees with Belot's suggestion that the medical community needs to do a lot more science-based research into all of pot's supposed health benefits.

"In particular, we need to learn more about the relationship between marijuana and cancer," especially if, in fact, it really is a beneficial one," he adds.