Sleep is one of the most essential physiological needs for humans. Growth and repair of worn-out body cells and tissues occur during sleep. Sleep is necessary for the proper functioning of almost every system in our bodies; it plays a role in brain development, metabolism, immunity, and emotional regulation. Sleep deprivation over a long period of time has been linked to increased risk of dementia, Alzheimer’s disease, insulin resistance, hypertension, depression, and immune system dysregulation. But for many, getting quality sleep is not that simple. This could be due to a primary sleep disorder, or it could be secondary, meaning there is an underlying issue causing the sleep disorder. The underlying issue could be a medical disorder, a mental health problem, or side effects of a drug. Sleep disorders can present in diverse ways; they can manifest as not getting enough sleep in terms of duration, they can manifest as fragmented sleep, they can manifest as finding it difficult to fall asleep despite being exhausted, uncontrollable sleepiness (narcolepsy), or never feeling refreshed regardless of how long the sleep is. This is because different key points in the sleep-wake cycle could be disrupted, resulting in different forms of sleep disorders. Among all these sleep disorders, insomnia happens to be the most prevalent. Globally, about 850 million adults ≥20 years (16.2% of the population) experience clinically relevant insomnia, and 415 million have severe insomnia. In the United States, 14.5% of adults reported having trouble falling asleep most days or every day, while 17.8% had difficulty staying asleep. The rise in the prevalence of insomnia, the health and economic consequences of insomnia, and the fact that some of the current pharmacological drugs for insomnia are not well tolerated have made stakeholders, both pharmaceutical companies and patients, seek other ways of improving sleep, and current research suggests that cannabis might hold some promise.
How Does the Body Regulate Sleep?
To understand the role of cannabis in sleep regulation, it would be helpful to have an overview of how the body regulates sleep. One of the best-known sleep regulators is the circadian rhythm. It is the body's 24-hour clock. This circadian rhythm is controlled by the suprachiasmatic nucleus in the hypothalamus, which responds to light and darkness. During the day, exposure to light keeps the brain alert. And at night, darkness triggers the release of melatonin. Melatonin signals the body to prepare for rest. In addition to the circadian rhythm, the body also depends on another important system: the endocannabinoid system. This system comprises small chemical messengers that are produced by our bodies. These messengers have receptors known as cannabinoid receptors (CB1 and CB2) to which they bind and exert their regulatory effect. CB1 receptors are abundant in areas like the hypothalamus and brainstem, which are areas that regulate neurotransmitters. Activating these receptors has been noted to increase slow-wave sleep (deep, restorative sleep).
The Role of Cannabis in Sleep Regulation
Cannabis research began decades ago. Cannabis contains more than 100 cannabinoids, which are chemical compounds that interact with our body’s endocannabinoid system (ECS). There has been growing interest in the role of cannabis in managing sleep disorders since it was discovered that cannabinoids like Δ−9-tetrahydrocannabinol (THC) and cannabidiol (CBD), which are extracted from the plant, can activate the endocannabinoid system and, in turn, regulate sleep. The results from early research done in the 1970s were mixed, but in general, suggested that cannabis could improve sleep when used for a short duration. They also noted that prolonged use could lead to withdrawal symptoms, which eventually result in relapse and an increase in dose to achieve a similar effect (tolerance).
Current Research
Though cannabis research is still in the early phase, it is gradually clarifying the role of cannabis in sleep. For now, tetrahydrocannabinol (THC) and cannabidiol (CBD) are the well-known cannabinoids, but others like cannabinol (CBN) are also gaining attention. Research has also begun to evaluate the non-cannabinoid components of cannabis, like terpenes, for their role in improving sleep.
Cannabidiol and Sleep
Cannabidiol (CBD) is a non-intoxicating component of cannabis that has been widely studied for its role in managing anxiety and sleep disorders. A clinical trial was published in The Permanente Journal. This study found that the majority of participants had lower anxiety levels, and two-thirds said that they noticed improvements in sleep after taking CBD for one month. From the result of this study, we can infer that low to moderate doses (≤25 mg/day) of cannabidiol may help people fall asleep by reducing anxiety and promoting relaxation, which indirectly improves sleep. At higher doses, cannabidiol acts as a sedative. It is important to note that these effects can vary between individuals, and more studies are needed for generalizable results.
Tetrahydrocannabinol and Sleep
Tetrahydrocannabinol (THC) is the main psychoactive compound in cannabis. It has a less straightforward relationship with sleep compared to cannabidiol. At low doses, THC might reduce the time it takes for a person to fall asleep (sleep latency). But chronic use of THC is linked to disrupted REM sleep and an increase in the risk of dependence. A 2017 review emphasized that though THC may have short-term benefits, its long-term use can impair overall sleep quality.
Cannabinol and Sleep?
Cannabinol (CBN) is the lesser-known cannabinoid that is often marketed as the “sleep cannabinoid.” Preclinical studies done in the lab or on animals suggest that it might have sedative effects, but evidence from human studies is limited. A recent study that explored whether cannabinol (CBN) alone could improve sleep quality found that 20 mg of CBN on its own helped to reduce the number of times participants woke up during the night and lessened overall sleep disturbances without causing daytime fatigue. But it did not make the study participants fall asleep faster.
The Entourage Effect
Instead of focusing on single cannabinoids, researchers are now exploring the entourage effect. This is the idea that the combination of cannabinoids and terpenes may be more effective for sleep than isolated compounds. Since each specific compound has an area of strength, it is postulated that when combined, they can act synergistically to give better results. For example, CBD may counteract some of the anxiety-provoking effects of THC, THC may aid sleep onset, and terpenes like myrcene and linalool could contribute calming effects. A study was done in 2021 to evaluate the safety and efficacy of a cannabinoid formulation (sublingual oil) that contained all three key cannabinoids: THC, CBD, and CBN. The results showed that the cannabinoid formulation was well-tolerated and participants noted some improvements in their symptoms. Other studies tried a combination of CBD and terpenes and found that they might be safe and efficacious for the management of insomnia.
What Does This Mean for Sleep Tinctures?
This means that an appropriate formulation of full-spectrum sleep tincture may be beneficial for people who seek holistic and natural alternatives to conventional sleep medications. It is important to note that cannabis research is still in its early stages. Many studies rely on preclinical data from laboratory and animal models or involve relatively small groups of human participants, which limits the strength of their conclusions. Regulatory barriers have previously slowed progress in cannabis research, but things have taken a different turn, and now there is a remarkable increase in the number of cannabis studies. Although more clinical trials are needed, preliminary evidence already points to the fact that full-spectrum cannabis products are better than isolates in the management of insomnia. If you are considering trying a cannabis sleep tincture, start low, go slow, and consult a healthcare professional, especially if you are taking other medications.