People produce endocannabinoids—similar to compounds found in marijuana—that are critical to many bodily functions

Over the past two decades, a great deal of attention has been given to marijuana—also known as pot or weed. As of early 2023, marijuana has been legalized for recreational use in 21 states and Washington, D.C., and the use of marijuana for medical purposes has grown significantly during the last 20 or so years.

But few people know that the human body naturally produces chemicals that are very similar to delta-9-tetrahydrocannabinol, or THC, the psychoactive compound in marijuana, which comes from the Cannabis sativa plant. These substances are called endocannabinoids, and they’re found across all vertebrate species.

Evolutionarily, the appearance of endocannabinoids in vertebrate animals predates that of Cannabis sativa by about 575 million years.

It is as if the human body has its own version of a marijuana seedling inside, constantly producing small amounts of endocannabinoids.

The similarity of endocannabinoids to THC, and…