fb-pixel Skip to main content
Daily Dose

No science for Obama’s recent pot claim


When President Obama declared in a recent New Yorker magazine interview that he doesn’t think pot “is more dangerous than alcohol,” he seemed to contradict his own administration’s policy that is firmly against the legalization of marijuana. He also seemed to indicate that the pot smoking he did in his teens had no major health impact.

“I view it as a bad habit and a vice,” he told the New Yorker’s David Remnick, “not very different from the cigarettes that I smoked.”

That’s a position a lot of teens take today — more teenagers smoke pot than cigarettes, according to a 2012 survey from the federal Centers for Disease Control and Prevention.


But there’s a scarcity of research to determine just how risky it is to use marijuana purely for recreational purposes — which is legal in Colorado and Washington.

“I don’t know if we have any definitive answers about cannabis use and its long-term health impact,” said Dr. Yasmin Hurd, a professor of psychiatry and neuroscience at the Icahn School of Medicine at Mount Sinai in New York. “It hasn’t been studied as much as cigarettes and alcohol.”

Hurd and drug policy researchers distinguish recreational use from medicinal use, which also hasn’t been well studied but has anecdotally been shown to ease pain and nausea. Marijuana dispensed for medical purposes was legalized last November in Massachusetts.

Even if smoking pot carries the same health risks as alcohol, as Obama claims, that doesn’t bring much comfort to Dr. Timothy Naimi, a substance abuse policy researcher at Boston Medical Center. “Excessive alcohol use is the third leading cause of preventable deaths in the US,” he said.

Regular marijuana use also has risks: One in six adolescents who use pot regularly will become addicted, according to Susan Weiss, associate director for scientific affairs at the National Institute on Drug Abuse. More than 6 percent of teens report in government surveys that they smoke marijuana nearly every day.


She and other public health officials are most concerned about adolescent use because adolescence is a crucial time for brain development. A 2012 Duke University study found that IQ scores dropped in teens who started smoking pot and continued into adulthood. Other research suggests the habit may interfere with memory and lead to an impairment in assessing dangerous risks.

And a new animal study conducted by Hurd and her colleagues suggests that marijuana use in teens could affect the programming of certain genes that increase drug addiction tendencies in offspring conceived years later.

The study, published Wednesday in the journal Neuropsychopharmacology, was conducted in rats who were exposed to THC — the active ingredient in marijuana — during their adolescence.

“They had the equivalent of a joint every few days and then stopped in early adulthood before giving birth to offspring,” Hurd said. “Their offspring were more likely to seek out heroin that was offered to them and to exhibit withdrawal symptoms when not given the drug compared with those born to rats given a placebo.” All of the baby rats were raised by nonbiological parents not exposed to any THC.

“It’s a very disturbing and intriguing finding,” Weiss said. “We’ve all been conscious of the fact that prenatal exposure to certain drugs and toxins can have long-term consequences, but now we’re seeing that what we do as teens — a vulnerable time of brain development — may have an impact on our future offspring.”


More research is needed to determine whether this finding applies to humans, but Weiss said legalization of marijuana use in some states has “added an amount of urgency” in terms of the institute’s priority to learn more about pot’s health effects.

While Obama shouldn’t be too worried about his daughters drifting toward hard drugs because of his past “bad habit,” he’s certainly smart to discourage them from trying marijuana. “I’ve told my daughters I think it’s a bad idea, a waste of time, not very healthy,” he said in the New Yorker interview.

Here’s a compelling argument against legalization of marijuana for pure pleasure: “With any substance — alcohol, tobacco — availability in the general society means more availability to youth,” Naimi said, even if there are age restrictions that prohibit young people from purchasing it.

What’s more, the potency of pot has increased over the past few decades, with a THC content that’s now about 15 percent in products seized during raids, according to Weiss, instead of 3 to 4 percent in the past. That could lead to more side effects like paranoia, rapid heart rate, and psychosis, she added. Deborah Kotz

Deborah Kotz can be reached at dkotz@globe.com. Follow her on Twitter @debkotz2.