There's a mechanism called the Endocannabinoid System inside the human body which is basically a set of cannabinoid receptors and the corresponding cannabinoids that activate them. Our body produces its own endocannabinoids to activate the cannabinoid receptors spread all over our body. This activation process helps to regulate vital bodily functions like appetite, sleep cycles, heart rate, body temperature, blood pressure, immune function etc. to maintain homeostasis, a state of equilibrium in the body. Everything is fine when our body produces enough endocannabinoids. But when it does not, it's not so nice.

Dr. Ethan Russo, a researcher on cannabinoids first proposed in 2001 that Endocannabinoid Deficiency might explain why certain medical conditions develop. Subsequent research have shown that underlying endocannabinoid deficiencies indeed play a role in migraine, fibromyalgia, irritable bowel syndrome and other treatment-resistant syndromes. Also, given the multitude of bodily functions that the Endocannabinoid System regulates, we shouldn't be surprised at all if a lot more health issues are linked with Cannabinoid Deficiency after further research.

Not to worry though, as Cannabinoid Deficiency can be suitably treated with Ganja, a widely available plant. The cannabinoids found in Ganja are very much like our own endocannabinoids and taking Ganja helps to make up for the deficient endocannabinoids and keep the health issues away. As legal barriers fall and scientific bias fades this will become more apparent. Sources.