Does marijuana affect your sense of smell

About cannabis, smell and cravings

After smoking weed, bags of chips and chocolate packs are often torn open with a giggle - cravings are a typical side effect of cannabis use. A study on mice now points to the background to this effect: If cannabinoid receptors in the olfactory system are activated, they trigger more odor perception and thus hunger. This relationship could possibly be used specifically for the treatment of eating disorders, say the researchers.

The reason why the active ingredient in cannabis, tetrahydrocannabinol (THC), causes relevant effects in humans is basically due to the fact that it resembles certain endogenous substances in us: the so-called endocannabinoids. There are still many unanswered questions about how the body's endocannabinoid system works. However, it has already been shown that it plays an important role in the transmission of signals in the nervous system. The function is based on an interaction of activators and receptors. Endocannabinoids are released in the body under certain conditions and then dock on special receptors, which in turn trigger signal cascades. It is already known that hunger is associated with the release of endocannabinoids in the brain. An earlier study had also shown in rats that the taste of high-fat food alone can trigger the production of endocannabinoids in the intestines and thus lead to increased hunger.

In order to pursue the question of the function of the endocannabinoid system in the context of the development of feelings of hunger, the researchers led by Edgar Soria-Gómez from the University of Bordeaux have now carried out studies on mice. All previous studies indicate that the endocannabinoid system performs similar functions in all mammals. Mice, for example, react to the administration of THC in a very similar way to humans - including the increased feeling of hunger.

Endocannabinoid System and Munching Mice

The researchers were able to show through their experiments that the appetite-stimulating effect of food scents is associated with the activation of endocannabinoid receptors in the olfactory bulb in fasting mice. This effect also resulted from the administration of exogenous cannabinoids, such as the THC of the marijuana plant. In addition, the activation of these sensors increased the odor perception and thus the hunger of the animals, the researchers report. In line with this, the effects could also be prevented by substances or measures that block the cannabinoid receptors in the olfactory bulb.


According to the researchers, the results suggest that the endocannabinoid system is also involved in the development of feelings of hunger in humans by influencing the olfactory system. This connection could possibly be used in a targeted manner: Perhaps substances that dampen the hunger-increasing effect of the natural endocannabinoid system could be used to treat problematic eating habits.

Original work by the researchers:

© - Martin Vieweg
February 10, 2014