Cannabinoids are a group of compounds that interact with the endocannabinoid system (ECS), a complex cell signaling network that regulates various functions and processes in the human body. The ECS consists of three main components: endocannabinoids, cannabinoid receptors and enzymes. Endocannabinoids are naturally produced by the body and act as neurotransmitters that bind to cannabinoid receptors. Cannabinoid receptors are present on the surface of cells throughout the body and mediate the effects of endocannabinoids and cannabinoids from external sources, such as the cannabis plant. Enzymes are responsible for synthesizing and degrading endocannabinoids.
The ECS is involved in many physiological and pathological conditions, such as pain, inflammation, mood, appetite, sleep, memory, immune response, fertility, pregnancy and neurodegeneration. The ECS is also a potential therapeutic target for various diseases and disorders, such as chronic pain, anxiety, depression, epilepsy, multiple sclerosis, Parkinson’s disease, Alzheimer’s disease and inflammatory bowel diseases.
In this article, we will explore the benefits of cannabinoids and endocannabinoids for human health, based on the current scientific evidence.
Pain Management
One of the most well-known benefits of cannabinoids and endocannabinoids is their ability to modulate pain perception and inflammation. The ECS plays a key role in regulating nociception, which is the process of sensing and responding to harmful stimuli. Endocannabinoids, such as anandamide and 2-archidonoyl glycerol (2-AG), can inhibit the transmission of pain signals by activating CB1 receptors in the central nervous system (CNS) and CB2 receptors in the peripheral nervous system (PNS) and immune cells. Cannabinoids from the cannabis plant, such as tetrahydrocannabinol (THC) and cannabidiol (CBD), can also produce analgesic and anti-inflammatory effects by interacting with cannabinoid receptors and other targets.
Several studies have shown that cannabinoids can be effective in treating various types of pain, such as neuropathic pain, inflammatory pain, cancer pain and postoperative pain. For example, a systematic review of 28 randomized controlled trials found that cannabinoids provided effective pain relief for patients with chronic neuropathic pain1. Another systematic review of 18 randomized controlled trials found that cannabinoids improved pain outcomes for patients with cancer-related pain
Mood Regulation
Another benefit of cannabinoids and endocannabinoids is their impact on mood regulation and emotional processing. The ECS modulates the activity of several neurotransmitter systems that are involved in mood disorders, such as serotonin, dopamine, glutamate and gamma-aminobutyric acid (GABA). Endocannabinoids can enhance mood by activating CB1 receptors in the brain regions that control emotional responses, such as the amygdala, hippocampus and prefrontal cortex. Cannabinoids can also affect mood by influencing the levels of serotonin, which is a neurotransmitter that regulates happiness, anxiety and stress.
Several studies have shown that cannabinoids can be beneficial for patients with mood disorders, such as depression and anxiety. For example, a randomized controlled trial of 24 patients with social anxiety disorder found that CBD reduced anxiety levels during a simulated public speaking test
Appetite Stimulation
Another benefit of cannabinoids and endocannabinoids is their role in appetite stimulation and energy balance. The ECS regulates food intake and metabolism by influencing the activity of several hormones and peptides that control hunger and satiety signals. Endocannabinoids can stimulate appetite by activating CB1 receptors in the hypothalamus, which is the brain region that controls feeding behavior. Cannabinoids can also increase appetite by enhancing the reward value of food and reducing nausea and vomiting.
Several studies have shown that cannabinoids can be useful for patients with conditions that cause appetite loss or cachexia, such as cancer, HIV/AIDS or anorexia nervosa. For example, a systematic review of 22 randomized controlled trials found that cannabinoids increased appetite and weight gain in patients with HIV/AIDS. Another systematic review of 13 randomized controlled trials found that cannabinoids improved appetite and quality of life in patients with cancer-related anorexia-cachexia syndrome. A case report of a 19-year-old female with anorexia nervosa found that CBD improved her eating behavior and body weight.
Sleep Quality
Another benefit of cannabinoids and endocannabinoids is their effect on sleep quality and circadian rhythms. The ECS regulates sleep-wake cycles by influencing the activity of several neurotransmitters and hormones that control sleep onset, maintenance and architecture. Endocannabinoids can promote sleep by activating CB1 receptors in the brain regions that regulate sleep, such as the basal forebrain, thalamus and hypothalamus. Cannabinoids can also improve sleep by reducing pain, anxiety and inflammation, which are common causes of insomnia.
Several studies have shown that cannabinoids can be helpful for patients with sleep disorders, such as insomnia, obstructive sleep apnea and restless legs syndrome. For example, a randomized controlled trial of 23 patients with chronic insomnia disorder found that CBD improved sleep quality and reduced daytime sleepiness. Another randomized controlled trial of 17 patients with obstructive sleep apnea found that THC reduced the severity of apnea episodes and improved subjective sleep quality. A case series of six patients with restless legs syndrome found that CBD reduced the frequency and intensity of leg movements and improved sleep quality.
Fertility and Pregnancy
Another benefit of cannabinoids and endocannabinoids is their involvement in fertility and pregnancy. The ECS regulates reproductive functions by influencing the activity of several hormones and factors that control ovulation, fertilization, implantation, placentation and parturition. Endocannabinoids can enhance fertility by activating CB1 receptors in the ovaries, uterus, fallopian tubes and testes. Cannabinoids can also affect pregnancy by modulating the development and function of the placenta and the fetus.
Several studies have shown that cannabinoids can have positive or negative effects on fertility and pregnancy, depending on the dose, timing and type of cannabinoid. For example, a systematic review of 15 studies found that low doses of THC increased sperm motility and fertilization rates in animal models. Another systematic review of 24 studies found that high doses of THC impaired sperm production and quality in animal models. A meta-analysis of 24 studies found that cannabis use during pregnancy was associated with low birth weight, preterm delivery and small for gestational age infants.
Conclusion
Cannabinoids and endocannabinoids are important modulators of various functions and processes in the human body. They interact with the ECS, a complex cell signaling network that regulates pain, mood, appetite, sleep, fertility and pregnancy. The ECS is also a potential therapeutic target for various diseases and disorders that affect these functions. Cannabinoids can have beneficial or detrimental effects on human health, depending on the dose, timing and type of cannabinoid. More research is needed to elucidate the mechanisms and optimal conditions for using cannabinoids as medicine.
References
3: Vučković S, Srebro D, Vujović KS, Vučetić Č, Prostran M. Cannabinoids and pain: new insights from old molecules. Front Pharmacol. 2018;9:1259.