The Buzz: The Science of the Munchies

The munchies is one of the most well-known and significantly reported side effects following cannabis use. Indeed, cannabis use is associated with eating a half-gallon of pistachio ice cream in one sitting and ordering a large pizza with a side of spicy chicken wings at midnight without a second thought. Even non–cannabis users are well acquainted with the idea that cannabis users are prone to snacking when under the influence of THC.

Stereotypes exist with good reason, typically because they hold some basis in fact. The fact is that cannabis stimulates appetite. It can certainly lead a consumer down the path toward overindulgence, which can be problematic. In a world where obesity is linked to 4.7 million deaths annually, a substance that increases appetite and promotes intake of junk food may appear to be a contributing factor.1

Stereotypes aside, the full story of how cannabis affects the waistline is just starting to emerge. Conventional wisdom suggests that appetite stimulation would cause cannabis users to weigh more than their nonuser counterparts. However, evidence from several large studies reveals a different story in which cannabis users weigh less than nonusers.

The Role of the ECS
The endocannabinoid system (ECS) plays a significant role in regulating food intake, energy homeostasis, and lipid metabolism.2 When cannabinoid receptors in the hypothalamus are stimulated by either endogenous cannabinoids or phytocannabinoids, hunger signals are transmitted, and ghrelin—the hormone responsible for increased appetite and food intake—is secreted.3 Off to the fridge one goes and munching ensues. The rest of the limbic system agrees with this move to intake food and stimulates warm fuzzy feelings. More munching ensues. All the while, cannabinoids stimulate CB receptors in the gut to mediate digestion. Eventually, the gastric mucosa and small bowel sends satiated signals to the hypothalamus by producing leptin, the hormone responsible for inhibiting appetite when individuals have devoured their chosen snacks. ECS activation is reduced, and the stereotypical subjects take a nap after they’ve cured their munchies.4,5

Survey Says: Cannabis Users Weigh Less Than Nonusers
A recent study conducted at Michigan State University and published in the International Journal of Epidemiology revealed that adults who smoke cannabis weigh less than do adults who don’t smoke cannabis. The researchers reviewed data from 33,000 participants of the National Epidemiologic Survey of Alcohol and Related Conditions (NESARC). In comparing body mass index (BMI) data of the participants, they found that cannabis users were at a normal, healthier weight than were nonusers and were more apt to stay at the healthier weight. They found that 15% of the cannabis users were considered to have obesity compared with 20% of nonusers.6

Another study published in the American Journal of Epidemiology indicated similar findings. The researchers used cross-sectional data from the NESARC and another representative epidemiological survey—the National Comorbidity Survey-Replication (NCS-R). The NESARC involved 43,093 participants and was conducted by the National Institute on Alcohol Abuse and Alcoholism. The NCS-R was an independent survey of 9,282 respondents conducted by the National Institute of Mental Health. Participants from the two studies were grouped into four categories of cannabis use: no use in the last 12 months, use at least once a year but less than once a month, use from once a month or more to twice per week, and use from three days per week to every day. The researchers found that prevalence of obesity was significantly lower in participants who reported cannabis use at least once a year compared with participants who reported no use in the last 12 months.7

Why Do Cannabis Users Weigh Less?
While researchers have yet to conclude why cannabis users weigh less than nonusers, theories backed by quality evidence are starting to materialize. A meta-analysis published in Cannabis and Cannabinoid Research in 2018 “revealed significantly reduced body mass index and rates of obesity in cannabis users, in conjunction with increased caloric intake.” The authors then provided a detailed theory as to why this paradox occurs and provided evidence to support their theory. They discussed the impact of the Western diet on the dysregulation of the ECS related to increased production of endocannabinoids N-arachidonoylethanolamine (AEA) and 2-arachidonoylglycerol (2-AG).8

The Western diet consists of an overabundance of calories from sugars, refined starches, grains, animal products, and a strongly elevated ratio of omega-6 to omega-3 polyunsaturated fatty acids. Omega-6 fatty acids convert to AEA and 2-AG; the overabundance of this fatty acid promotes overstimulation of the CB1 receptor, thereby increasing intake, storage, and conservation of energy. Basically, overstimulation of the CB1 receptor disrupts homeostasis by dysregulating glucose and lipid metabolism, which promotes weight gain and increased body mass.8

Conversely, cannabis use, specifically THC, down-regulates CB1 receptor sensitivity to AEA and 2-AG, diminishing the negative impacts associated with increased omega-6 fatty acids as well as other foodlike substances. Down-regulation of the CB1 receptor is thought to increase metabolism and reduce energy storage, resulting in lower BMI. The main driver of this consideration points to the evidence that cannabis users intake more calories when experiencing regular bouts of the munchies yet tend to weigh less than nonusers.8

Can Cannabis Help People Lose Weight?
Although these studies indicate that the ECS may be a potential target for treatment of obesity and diseases associated with increased BMI, it’s not a foregone conclusion that regular cannabis use will help a people meet their weight loss goals—especially if our stereotypical cannabis users fill up on processed food every night during their binge-watch and chill time. Consuming a nutrient-dense diet, moving the body in a vigorous activity for a minimum of 30 minutes most days of the week, staying adequately hydrated, and getting enough sleep are more apt to help them reach their weight loss goals and maintain a healthy body mass. Perhaps in the near future, cannabis will be an essential weight loss supplement. For now, cannabis users motivated to drop a few pounds may want to consider stocking their pantries with nutrient-dense snacks to ensure healthful munching.

— Marissa Fratoni, BSN-RN, LMT, RYT, INHC, is a holistic nurse and multidiscipline health practitioner specializing in women’s health and behavior health and further specializing in cannabinoid therapeutics She’s well versed in complementary healing modalities including massage therapy, yoga, and integrative nutrition. An advocate for the therapeutic use of cannabis, her published work in the cannabis space can be found at holisticnursemama.blog.

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