Lots of people say they smoke weed because it makes them feel less anxious. Though lots of stoners can tell you that the stuff works, the science to back it up hasn’t really been clear—but a new study has even the director of the National Institutes of Health suggesting that marijuana can be used to relieve anxiety.
In a blog post today, NIH director Francis Collins wrote that recent studies have shed some light on why marijuana relieves anxiety and offered up some new evidence that it actually works. The key, he says, is that THC in marijuana interacts with the type 1 cannabinoid receptors in the brain, which is “critical for normal brain development and activity, immunity, and the physiological regulation of stress responses.” But, in order for the marijuana-anxiety relief link to have some sort of biological basis (as opposed to a mere placebo effect), these affected CB1 receptors would have to be found in the central amygdala, “a region of the brain that, among other things, controls anxiety and response to stress.”
In a mouse study, researchers at Vanderbilt University found that there are indeed CB1 receptors in the central amygdala of the mouse brain. Furthermore, they found that marijuana was able to calm these receptors down, which, in turn, probably calms you down.
“The researchers found that when endocannabinoids interacted with CB1 receptors of neurons located in the central amygdala, the natural chemicals reduced the excitability of these brain cells. This suggests that THC and/or other external cannabinoids found in marijuana may also serve to reduce anxiety by binding to CB1 receptors in the amygdala, rendering neurons less active,” Collins wrote. That’s promising, and it’s probably the strongest scientific support ever discovered that marijuana eases anxiety. That’s in mice, however, so Collins says that “this hypothesis must be confirmed by further studies.”
That’s a pretty big deal—Collins is one of the most important scientists in the country, and his support of a study like this could be hugely important in legitimizing further studies of the issue. The NIH and its associated National Institute on Drug Abuse have already acknowledged the medicinal effects of marijuana for treating pain and nausea, but have been careful not to back it as an anxiety treatment. In fact, NIDA’s page on marijuana suggests that the drug can cause anxiety (to be fair, anyone who knows this feeling can tell you that’s true).
“Associations have also been found between marijuana use and other mental health problems, such as depression, anxiety, suicidal thoughts among adolescents, and personality disturbances, including a lack of motivation to engage in typically rewarding activities. More research is still needed to confirm and better understand these linkages,” NIDA’s site says.
Collins doesn’t say what the next step for the NIH will be, but if you smoke weed for stress, now you know why it works.