I've seen this type of study come up from time to time.
There are a number of flaws to consider.
$1:
Neither marijuana nor the main psychoactive component of the plant, THC, has been shown to cause cancer.
There are, however, substances in marijuana that can be very harmful to a person, according to previous studies on the drug.
Negative health effects induced by smoking marijuana, such as chronic bronchitis, have been well documented, as have other negative health effects.
A 2007 study from New Zealand, for example, examined the effects of cannabis on lung capacity. The results suggested that marijuana smoke compromised lung efficiency between 2.5 and five times more than tobacco smoke.
I've been smoking the stuff since the age of 17 and in the 12 years I've been smoking it, I never coughed up any green or black crap, I was never short of breath, I could do everything I always could do.
I just started smoking tobacco about three or four years ago and within a week of smoking tobacco I was coughing up piles of crap and I have noticed a slight change in my breathing patterns.
If I stop smoking tobacco for a week or two, like I have done in the past, my lungs clear up. I keep smoking pot, but there's nothing coming up, no weezy breathing, nothing.
Then I start back with the tobacco and guess what?
Second issue:
Other studies I have come accross that talk about more tar in weed, or whatever to make it worse then tobacco have never been clear on what they use as a source to gain this information.
Some say they study a comparison to cigarettes to joints, but let's look a little deeper into that shall we?
• A joint can consist of all weed, or a mix of tobacco and weed which most do to save money.
• Some people roll joints without any filter, while others, such as myself, use some rolled cardboard for some form of a filter. Nothing similar to the filters on cigarettes, thus more smoke passes through that's not filtered.
• Those joints with tobacco would have the same type of tobacco in regular cigarettes going into your lungs.... without a filter, thus obviously a joint would seem a hell of a lot worse.
What about Pipes? Lungs? Vaporizers?
Third point:
^ As soon as one of these three guys dies off and it's found they died from long term pot use, I may take some of this seriously.
Since Willie Nelson is currently 76 years old, Chong 71 years old and Cheech is 63 years old and have a long history of smoking pot.... you'd think these guys would be laid up in a hospital bed by now hooked up to an iron lung based on these studies.
Instead, they're still doing what they love.
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