Cannabis acts on the body and mind by binding to what are called cannabinoid receptors, long, ropy proteins that weave themselves into the surfaces of our cells and process THC, as well as other organic chemical compounds. "Scattered throughout the body, cannabinoid receptors come in two varieties, called CB1 and CB2—most of your CB1 receptors are in your brain, and are responsible for that 'high' feeling when you smoke pot." CB2 receptors are associated with the immune system and situated throughout the body, explaining why cannabis reduces swelling and pain.
What's the Big Idea?
Explaining the munchies: CB1 receptors located in your brain's hypothalamus, which regulates appetite, are responsible for receiving the 'I'm hungry' message from your body's cannabinoids. When you ingest THC, you are artificially boosting the number of cannabinoids in your body, creating a stronger than usual 'I'm hungry' feeling. Explaining why cannabis makes you forgetful: The effects of THC on the hippocampus, the part of your brain most associated with memory, resembles a temporary lesion. The effect is consistent with an abundance of CB1 receptors in the hippocampus.