Can Marijuana Kill You? What You Should Know About Weed and Its Health Risks

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What is the worst-case scenario from smoking too much weed — something minor, like an insatiable appetite from the munchies, or something much, much worse? Horror stories of marijuana that lead to someone's death have played out in the media from time to time, which can naturally lead to some concern. However, what are the actual ramifications of smoking weed? 

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Can it damage lungs? One of the biggest claims for marijuana's risks is the correlation between smoking weed and the various pulmonary diseases that could result from it. However, there is little evidence to suggest that smoking pot has intense, adverse effects to someone's lungs, especially when compared to smoking tobacco. In fact, a 2012 study by the Journal of the American Medical Association, which followed 5,115 young adults for two decades, found that "occasional and low cumulative marijuana use was not associated with adverse effects on pulmonary function."

Conversely, tobacco has been proven in many studies to have much greater effects on the lungs, with higher death rates. According to the National Heart, Lung and Blood Institute, more than 120,000 Americans are killed by chronic obstructive pulmonary disease per year. In an additional report by the Centers for Disease Control and Prevention, the deaths were almost always caused by cigarette smoking, estimating roughly eight of 10 COPD deaths are caused by it. In contrast, there isn't even a mention of marijuana in the report. 

Long-term effects: Additionally, the long-term side effects have been, thus far, hard to gauge. In a 2003 editorial published in the British Medical Journal, the article detailed a Swedish study of more than 45,000 males, which showed no increase in the mortality rate of pot smokers within a 15-year time frame compared to non-smokers. 

Even relative to other drugs, it is considerably more harmless. According to the American Scientist, while marijuana is likely more risky to smoke than consume, a user would have to go to great lengths to put their life in danger — anywhere from 100 to 1,000 times the dose that would get someone high. "My surmise is that smoking marijuana is more risky than eating it but it is still safer than getting drunk," Robert S. Gable — professor of psychology at Claremont Graduate University — wrote for the American Scientist

It can lower your IQ — depending on your age: Cognitively, marijuana can make an impact on young adults and teens, according to several studies. "It disrupts the development of circuits," Dr. Paula Riggs — professor of psychiatry at the University of Colorado — said in an interview with ABC News. "The latest study shows that regular use when you're an adolescent is associated with a 6-to-8 point reduction in IQ." 

It can be linked to car accidents: It's not always the act of smoking that can be harmful, but rather, what someone does when they're high. According to a 2013 study from the American Journal of Epidemiology (h/t the Week) , reported by the Week, car accidents that were linked to marijuana have tripled in the last decade, while weed accounts for roughly one-third of all traffic fatalities. 

We'll know more over time: Clearly, the longstanding effects of marijuana use will shed more light as studies continue to come out, and the drug continues to be legalized to some extent across the country.