Sleep is essential for human survival; it affects an individual’s physical and mental health. Although the amount of sleep required varies throughout a person’s lifetime, the quality of it remains essential. Quality sleep restores the body, consolidates memories, supports emotional regulation, and plays a key role in maintaining the immune system. When sleep quality is compromised—such as in cases of insomnia—it can significantly disrupt daily life, prompting many to seek alternative remedies for relief.
One substance often misrepresented as a sleep aid is marijuana; however, research consistently shows that tetrahydrocannabinol (THC) interferes with the very sleep processes it claims to improve. A recent randomized controlled trial examining the effects of a single dose of THC and cannabidiol (CBD), the two primary compounds in marijuana, on individuals with clinical insomnia raised serious concerns about using marijuana as a treatment for sleep problems.
THC and REM sleep
In this study, those who took a one-time dose of 10mg of THC and 20mg of CBD experienced significantly less total sleep time and spent less time in rapid eye movement (REM) sleep, the phase associated with dreaming, emotional processing and memory consolidation, supporting previous research that pointed to THC disrupting deep REM sleep. THC also disrupted restorative stages, meaning that individuals may fall asleep faster but may never get the kind of sleep the body truly needs.
Those who took this THC and CBD combination also took about an hour longer to reach REM sleep compared to placebo. Studies have shown that the suppression of REM sleep can have long term consequences. While in this study a single dose did not affect next-day function, researchers cautioned that regular use may lead to tolerance and eventual withdrawal symptoms that could lead to worse quality sleep over time. Withdrawal from marijuana can also cause more sleep issues that may lead to relapse, adding challenges for people struggling with substance use or mental health.
While CBD is often marketed as the “calming” component of marijuana, in this formulation it may have intensified THC’s effects due to unknown metabolizing processes of both substances together. As marijuana and CBD products become more widely available and socially accepted—often under misleading claims—more people may turn to them as “natural” sleep remedies. However, as this study underscores, natural does not necessarily mean safe or effective. Just because something is derived from a plant does not mean it is harmless or beneficial.
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Sources:
National Institute of Neurological Disorders and Stroke. (n.d.). Brain basics: Understanding sleep. National Institutes of Health. https://www.ninds.nih.gov/health-information/public-education/brain-basics/brain-basics-understanding-sleep
Suraev, A., McGregor, I. S., McCartney, D., Marshall, N. S., Kao, C.-H., Wassing, R., D’Rozario, A. L., Wong, K. K. H., Yee, B. J., Sivam, S., Kevin, R. C., Vandrey, R., Irwin, C., Gordon, C. J., Bartlett, D., Arnold, J. C., Grunstein, R. R., & Hoyos, C. M. (2025). Acute Effects of Oral Cannabinoids on Sleep and High-Density EEG in Insomnia: A Pilot Randomized Controlled Trial. Journal of Sleep Research.32(4), e70124. https://doi.org/10.1111/jsr.70124
