By: Chris O'Shea
Anyone who has smoked a joint or taken a hit off a bong knows what the munchies are. It's that feeling of being so hungry that even 7-11 sausages look enticing. The munchies make you eat everything in sight, and really, really enjoy it, too. It's a completely authentic phenomenon. Yet scientists have been unable to really figure it out. Until now. A group of experts have found that THC makes our brains fire up its scent region, and next thing you know you're chowing down.
As most know, pot is powered by Tetrahydrocannabinol (also known as THC). This is what makes you feel odd or amazing, depending on your viewpoint. But a group of neuroscientists — led by Giovanni Marsicano of the University of Bordeaux — wanted to find out exactly how and why THC gives us that munchie feeling. Of course they turned to mice. The team gave some mice THC while monitoring their brains. They found that the THC activated the receptors in the brain's olfactory bulb, the part that controls our ability to smell and taste food. When the THC impacted the olfactory bulb, the mice smelled and taste receptors went off the charts. They simply couldn't help themselves.
"The scientists began by exposing mice to banana and almond oils as a test of sensitivity to scent," explains Smithsonian magazine. "When they did so, the mice sniffed the oils extensively at first, then stopped showing interest in them, a well-known phenomenon called olfactory habituation. Mice that were dosed with THC, however, kept on sniffing, demonstrating an enhanced sensitivity to the scents. These THC-dosed mice also ate much more chow when given the chance, showing an increased appetite."
Think about smelling freshly made bread. Doesn't that make you want bread? Even if you're not exactly hungry at the moment? That's essentially what the THC is doing to you when you get the munchies. "Our study shows that both exogenous and endocannabinoids can disinhibit circuits of the olfactory bulb, which is the primary brain region mediating the sense of smell," Marsicano explained in an email interview with the Canadian newspaper the National Post. "Like that, the odours appear stronger to the subject."
This might not be news to stoners. After all, they likely realize that the shriveled 7-11 sausage isn't actually good smelling or tasting. The cool thing about this study is what it might mean for those with eating disorders, like anorexia. If scientists can target the exact portion of the brain that makes people hungry, they could potentially curb unhealthy behaviors.
"Many feeding disorders are accompanied by altered perception in general. For instance anorectic people see themselves as fat,” Marsicano told CBS. "Smell is particularly linked to food intake and is particularly altered in different diseases. Obese people tend to be more attracted by food odors' smell and its regulation by the cannabinoid system could represent a future target for therapies against these and other diseases."
[Image via Flickr - Khairil Zhafri]