Roughly half of Americans now live in states with some form of legal pot, recreational or medical. As legalization spreads, teens perceive that pot is less and less risky. (Most high school seniors don’t think regular pot smoking is very harmful, with only 36% saying that regular use puts people at great risk compared to 52% five years ago.)
It’s true that most healthy adults — excluding pregnant women — can use pot occasionally or even regularly without serious health risks. But the same does not appear to be the case for young people whose brains are still developing into their 20s.
Pot is addictive. One-in-11 adult consumers exhibits symptoms of addiction; the rate appears higher for young people. (Though pot remains one of the least addictive commonly used drugs.) That means pot can take priority over responsibilities at home, school, work or with friends. Long-term users may want to cut back or quit, but they don’t always follow through, as they report irritability, sleeplessness, decreased appetite and anxiety.
Chart 1: Addiction rates of Marijuana compared to other substances (legal and illegal)
Pot, particularly strong pot, appears to contribute to psychotic episodes and schizophrenia. To be clear, there is not conclusive evidence that pot causes schizophrenia. But evidence of a link is mounting in observational studies. A recent British study bolstered the connection between stronger weed and psychosis, finding that people who smoked potent weed daily had five times the normal risk of suffering a serious psychotic episode; weekly users had triple the risk. The risks, though remain relatively small, on the order of 1-in-1,500 for young men who are heavy users.
Chart 2: Risk of first episode psychosis to cannabis users
Pot impairs memory and learning and may be linked to long-lasting cognitive impairment and IQ loss up to 8 points for heavy users who started in adolescence. (The latter part is perhaps the most concerning in pot science, but it is only correlational and subject to debate.)
And the potency of pot has increased in recent years (see 3rd chart). Frankly, no one knows what increased potency means for sure and savvy users can simply titrate to get their buzz by consuming less. But given the recent British study on strong weed and psychosis, this could be a significant risk factor for some.
Chart 3: Marijuana potency in the United States over time
Marijuana advocates, meanwhile, have stressed the drug’s safety, some going so far as to say pot is not harmful.
Steve DeAngelo, a well-known marijuana advocate recently tweeted: “Nobody with a brain seriously believes cannabis is harmful, Choomie.” (It’s not an entirely uncharacteristic statement from DeAngelo. He also recently tweeted, “Cannabis doesn’t hurt Intelligence but lying ‘scientists’ do.”)
Who is DeAngelo? He’s the CEO of the nation’s largest medical marijuana dispensary, one of the movement’s most visible activists, and 4th Most Influential Cannabis Business Executive, according to one list (the 1st three are not industry executives) http://www.stevedeangelo.com/cannabisbusinessexecutive-com-fortune-500-industry-today-cannabis-business-executive-100/
So while he often adopts a rebel’s stance, he is a businessman with a financial interest in promoting marijuana use and anti-science propaganda. The federal Department of Justice initiated in 2012 forfeiture proceedings against DeAngelo’s Harborside dispensary, which does $25 million a year in sales, on the grounds that it had grown too big.
Bob Young, Tomer Weller
Bob and Tomer, nicely done. The charts really anchor your piece, and you do a great job of diminishing the credibility of the advocate on the other side of your argument.
You scared me with very good evidence, good links, and well argued points.
Kitty, I love your film and your sharp film. Why can’t I find it posted?
Bob
PS: You shouldn’t be too scared unless you’re concerned about a teen with a heavy habit. Even then, Barack Obama was a prodigious toker in high school and he turned out OK. There’s so much we still don’t know.
Kitty, meant to say “sharp humor,” as you had so many of us laughing out loud.