“Cannabinoid Deficiency and Its Impact on Human Health and Disease, Part 1” (Townsend Letter, July 2017) described how the botanical Cannabis, a plant long valued for its many medicinal and industrial uses, became illegal and the political and financial pressures against its use that continue to this day.

In Part 2 of this three-part article, Dr. John Desnoes and Sandra Kischuk give a detailed overview of the many cannabinoid studies that led to new understandings about brain function and the effects of cannabis. Researchers discovered cannabinoid receptors in the brain as well as naturally-occurring endocannabinoids, made in the body from fatty acid precursors. The human brain has more cannabinoid receptors than any other type of neurotransmitter receptor. “Endocannabinoids and their receptors modulate a variety of physiological processes in the brain; movement, nociception (the nervous system’s response to harmful or potentially harmful stimuli), brain reward, learning and memory, feeding, and emesis (vomiting),” explain the authors. “Peripheral processes impacted include those involved in immune regulation, the cardiovascular system, the reproductive endocrine processes, and energetic metabolism control.”

The human body makes its own endocannabinoids, given the right nutrients. Nutritional deficiencies and prolonged stress, however, disrupt endocannabinoid tone, which leads to detrimental effects on multiple physiological processes and on brain function. Prior to 1937, cannabis was legally used as a medicine, and the hemp plant provided livestock fodder for farm animals that supply meat, eggs, and dairy products.

This overview of the body’s endocannabinoid system in Part 2 explains why cannabis has so many and such varied therapeutic effects.