Researchers Identify How Cannabis Stimulates Appetite

The animal study was designed to investigate how cannabis use alters eating behavior.

While cannabis has long been acknowledged for its appetite-stimulating properties, up until now little has been understood on how cannabis and its compounds alter eating behavior. In a new animal study shared last week at the Society for the Study of Investigative Behavior, researchers from Washington State University were able to gather some evidence on how cannabis triggers hunger hormones.

“We all know cannabis use affects appetite, but until recently we’ve actually understood very little about how or why,” said Jon Davis, Ph.D., researcher in the Department of Integrative Physiology and Neurosciences at Washington State, in a statement. “By studying exposure to cannabis plant matter, the most widely consumed form, we’re finding genetic and physiological events in the body that allow cannabis to turn eating behavior on or off.”

In the study, Davis and his colleagues exposed rats to controlled doses of marijuana vapor. The rats were first separated into four categories, including:

  • A control group that was not exposed to marijuana vapor
  • Those on a “normal” diet, free to eat whenever they wanted
  • Those that ate enough to be more than full
  • Those that were forced to fast for 48 hours prior to exposure

While rats in the control group maintained regular eating habits, appetite was stimulated all three groups of rats exposed to the marijuana vapor. Regardless of prior eating habits, after being exposed to the marijuana vapor, the animals started to eat small meals every couple of hours.

“We found that cannabis exposure caused more frequent, small meals,” stated Davis. “But there’s a delay before it takes effect.”

It was the two-hour delay that lead the researchers to the cause of appetite stimulation. They went on to discover that the marijuana triggered a surge in ghrelin, a hormone released when the stomach is empty to signal to the brain that it’s time to seek out more food. To confirm the involvement of ghrelin, the researchers gave rats a second drug that prevents the ghrelin surge and found that it prevented the appetite-stimulating properties of cannabis.

The researchers also discovered that cannabis alters how the brain responds to ghrelin. Cannabis changed the genetic activity of brain cells in the small region of the hypothalamus that is responsible for sensing ghrelin.

vaping marijuana appetite

Implications of Findings

The effect of marijuana on appetite has huge implications for patients managing serious diseases and conditions that cause appetite suppression.

Extreme appetite loss leads to malnutrition, which reduces quality of life and slows recovery. The study’s findings could lead to better cannabis-based treatments for patients diagnosed with cachexia related to cancer, HIV and AIDS, heart disease, and some metabolic disorders.

The Washington State University researchers explained that they used controlled doses of marijuana vapor because it most closely mimics how people often consume cannabis.

“That was pretty powerful to us,” Davis explained in an interview with Inverse. “It shows us, okay, this is getting really close to what it would look like for a patient who hasn’t been able to eat and lost a lot of body weight.”

Davis and his colleagues intend to further investigate the therapeutic applications of marijuana and its compounds for appetite loss.

“Something that we want to pursue in my lab is seeing whether the effect of THC concentrations could cause different results — meaning, maybe they would eat a little sooner or delay feeding a little longer,” said Davis. “Having said that, I’m absolutely confident that when people are going to inhale or vaporize marijuana, they are going to have an increase in appetite.”

Read More Cannabis Research

This latest study on cannabis and appetite, “Investigating the Neuroendocrine and Behavioral Controls of Cannabis-Induced Feeding Behavior,” is currently under review.

Thousands of studies on cannabis and its therapeutic potential for various conditions and symptoms have been completed. You can learn more about those findings through the Medical Marijuana, Inc. education page. We also welcome you to keep up with the latest studies as their published through our news page.