CBD is the second most abundant compound in the cannabis sativa plant, and many studies suggest it may indirectly benefit sleep. In fact, CBD—which doesn’t cause the intoxicatingly psychoactive “high” associated with delta-9 tetrahydrocannabinol (THC)—might help people with different sleep disorders, including insomnia and restless leg syndrome, as well as other conditions known to negatively impact sleep, according to research.
For instance, CBD may help people relax by easing anxiety and pain, two factors that may make it difficult for someone to fall or stay asleep, says Dr. Strachan.
Insomnia
The hypothalamus plays a role in several sleep-related functions, including regulating body temperature and synchronizing sleep patterns. CBD can help people with insomnia because it works with the hypothalamus to regulate stress, says Dr. Whitelocke. “Insomnia results from an overactive stress reaction that’s spilling into a rest time when we’re not trying to process conscious trauma,” he adds. “CBD can suppress this dysregulated cycle of stress hormone overactivation and equalize the sleep and wake rhythm through counteracting hormones.”
In a study examining the effects of cannabis on insomnia, researchers found CBD more effectively decreased symptoms of insomnia than delta-9 THC, which is the most abundant active constituent in the cannabis sativa plant that has an intoxicatingly psychoactive effect[2].
Circadian Rhythm Disorders
Circadian rhythm disorders, also known as sleep-wake cycle disorders, occur when the body’s internal clock, which dictates when you fall asleep and when you wake up, is misaligned with your environment. Circadian rhythm disorders can develop when there are changes in sleep habits, often due to travel or work, or as a byproduct of a medical condition, aging or genetics.
CBD may improve both the quality and quantity of sleep by ensuring the body progresses through the normal stages of sleep and REM sleep without undue interruption, which would help people with circadian rhythm disorders, says Dr. Whitelock. “CBD’s action on cannabinoid receptors initiates a cascade of events that culminates in a more natural timing of sleep relative to the diurnal rhythm of night and day,” he explains. However, more research is needed.
CBD can be especially helpful for people like nurses who experience circadian rhythm disorders due to shift work, where sleep windows change depending on a person’s work schedule.
Anxiety
Many studies have found CBD to be a potential treatment for anxiety disorders. While more research is needed, studies link CBD use to improved sleep due to its ability to decrease anxiety.
“CBD’s well-established role in reducing anxiety—without causing stony lethargy that can accompany THC products—makes it an ideal tool to calm intrusive thoughts before laying down to sleep,” says Dr. Whitelocke. More specifically, CBD acts on the endocannabinoid receptors in the limbic system—a set of brain regions known to play a role in many important functions, including the regulation of emotions, storage of memories, sexual arousal, olfaction (or our sense of smell) and forming of learning patterns. When the limbic system is out of equilibrium, such as when an intrusive memory leads to anxiety and insomnia, CBD activates the ECS to help repress that memory and, consequently, facilitate sleep. “By restoring hormone balance,” says Dr. Whitelocke, “CBD acts as the great equalizer.”