Marijuana Smoking Doesn't Kill
Illegal Herb Not Harmless, but Data Show No Link to Death
Sept. 18, 2003 -- Marijuana smoking isn't harmless, but at
least it won't kill you.
It's been feared that marijuana smoke, like tobacco smoke,
causes cancer and heart disease. The evidence
argues otherwise, writes Stephen Sidney, MD, associate director for research
for Kaiser Permanente, Oakland, Calif., in the Sept 20 issue of The British
"Although the use of [marijuana] is not harmless, the current
knowledge base does not support the assertion that it has any notable adverse
public health impact in relation to mortality," Sidney concludes.
No Marijuana Deaths in 2 Large Studies
Sidney points to two large studies. The first is from (where
else?) California. A large HMO looked at 65,177 men and women age 15-49. Over
10 years, marijuana users died no sooner than nonusers.
The second study looked at 45,450 Swedish army conscripts. They
were 18-20 years old when asked about marijuana use. Fifteen years later, the
marijuana users were just as likely to remain alive as nonusers.
And since marijuana smoking can't kill outright -- there's no
such thing as a fatal marijuana overdose -- short-term use isn't deadly.
Long-term use can't be good for you. But Sidney notes that most marijuana
smokers don't become long-term users.
One worry about marijuana smoke is that it is inhaled, and
held, deep in the lungs. But the typical user smokes only one marijuana
cigarette -- or less -- a day. Tobacco users often smoke 20 or more cigarettes
daily. Moreover, tobacco contains nicotine, a highly addictive substance.
Marijuana, Sidney concludes, is less likely to harm than tobacco.
A 2001 study suggested that marijuana smoking increases the
risk of heart attack in the hour
immediately after smoking. But this seems to be the case in no more than
one-fifth of 1% of heart attacks -- a very rare risk indeed.
More Marijuana Deaths in the Future?
Marijuana users shouldn't cancel their life insurance policies
just yet. Sidney warns that longer-term data may indeed show that marijuana
smoking eventually raises the risk of premature death.
And if marijuana is legalized, long-term use may become more
common. If this is the case, there certainly will be more long-term effects of
SOURCE: Sidney, S. The British Medical
Journal, Sept. 20, 2003; vol 327: pp 635-636.