More than a third of American adults fail to get up to seven (7) hours of sleep daily.[1] Because of this, more people are embracing sleeping aids, including cannabis, to fix their shut-eye problems.
The expanding use of cannabis for sleep has led to heightened concern among experts about potential adverse effects.
Remarkably, a new study confirms long-held suspicion that extended cannabis use could hurt sleep and memory.[2]
The Cannabis, Sleep and Memory Research
In a brilliant new study published in the American Journal of Drug and Alcohol Abuse, scientists from the University of Texas examine the impact of sleep on the memory of cannabis users.[2]
They also tested if factors like sex influenced the effect of sleep on the cognitive function of cannabis users.
Concerning the justification for the research, Dr. Francesca Filbey, the lead author, noted that prior evidence regarding the link between cannabis use and sleep had been mixed so far.
Experts thought that the conflicting results might have something to do with other factors, like sex or the age at which cannabis was started.[2]
For example, studies show that long-term cannabis use affects sleep more in women than in men, especially in women who started at an early age and after a significant period of abstinence.[7]
Given the documented disparities in sleep-wake cycles between men and women, it was assumed that a person's sex could influence the relationship between sleep and other factors.
In this case, experts believed that cannabis use could exacerbate underlying sex-specific effects on sleep.
For the study, the researchers included 141 persons with cannabis use disorder (defined as using cannabis more than five (5) days per week in the preceding year) and 87 non-cannabis users.
In addition to doing various cognitive tests measuring verbal memory, spatial learning, and overall memory function, participants also indicated how often they had trouble sleeping in the previous week.
After collecting data from both groups, the researchers compared and contrasted the two data sets. The results showed that compared to the non-user group, cannabis users reported more sleep problems, which in turn led to impairments with visuospatial memory.
Surprisingly, the study's findings revealed that sex did not modify the effect of sleep on the memory of the participants who use cannabis.
Concerning the study's relevance, Dr. Filbey emphasized that the effect of cannabis use on sleep and memory had previously been researched separately.
"Although sleep is one of the most common reasons people use cannabis, our findings indicate that long-term cannabis use leads to decreased sleep, which is associated with poorer memory," Dr. Filbey noted.
Regarding the next steps, Dr. Filbey proposed that the study's findings be used to enlighten cannabis users, health professionals, and policymakers about the potential consequences of cannabis use as a sleep aid.
Understanding Sleep and Cannabis
The impact of cannabis on sleep has generated a lot of controversy among experts. While many people say that cannabis improves their sleep quality, research findings are mixed.
A study by researchers at the University of New Mexico, where over 400 people with insomnia were given medical-grade cannabis, found that several of the participants reported feeling a marked improvement in their sleep quality.[3]
Conversely, a French study that examined the association between cannabis use and sleep problems among university students discovered that insomnia was more frequently reported by the students who use cannabis compared to the non-users.[4]
Also, the study noted that those who took cannabis more regularly had a significantly higher insomnia risk compared to those who took it less frequently.[4]
Furthermore, some studies have found that people who use cannabis may spend less time in rapid eye movement (REM) sleep.[5]
Because dreams happen more often during REM sleep, this could help people with PTSD (who may have excessive and frightful nightmares) sleep better.
But REM sleep is also essential for processing emotions and making new memories stick, which marijuana could negatively influence.
How Does Cannabis Influence Sleep?
Cannabis is believed to influence sleep because of the ability of its active biochemicals, called cannabinoids, to bind to specific brain receptors that mediate sleep.
By binding to these receptors, cannabinoids can dampen the brain's arousal mechanism, raise the blood levels of sleep-inducing chemicals, or stimulate the arousal centers, preventing sleep.
Cannabidiol (CBD) and tetrahydrocannabinol (THC) are two of the many active ingredients found in cannabis.[6]
Although THC is sedative primarily, it can also have the opposite effect on some users, particularly those who are new to cannabis or who are taking massive doses.
In such instances, using cannabis in the hours leading up to bedtime can lengthen the time it takes to initiate sleep. In contrast, CBD seems to have an energizing effect at low dosages and a soothing effect when taken in large quantities.
What’s the Takeaway?
The array of conflicting evidence on the impact of cannabis on sleep can make it difficult for people to decide if it is a good sleep aid option for them.
If you are planning to use cannabis for your sleep, it is best to speak to your sleep doctor about it before starting.
Your doctor can provide the best advice based on your specific needs and explain the various sleep aid options accessible to you.
References
- Centers for Disease Control and Prevention. (September 7, 2022) Sleep and Sleep Disorders.https://www.cdc.gov/sleep/index.html
- Brown, T., Ackerman, R. A., Kroon, E., Kuhns, L., Cousijn, J., & Filbey, F. M. (2024). The role of sleep in the link between cannabis use and memory function: evidence from a cross-sectional study. The American journal of drug and alcohol abuse, 50(4), 547–556. https://doi.org/10.1080/00952990.2024.2362832
- Vigil, J. M., Stith, S. S., Diviant, J. P., Brockelman, F., Keeling, K., & Hall, B. (2018). Effectiveness of Raw, Natural Medical Cannabis Flower for Treating Insomnia under Naturalistic Conditions. Medicines (Basel, Switzerland), 5(3), 75. https://doi.org/10.3390/medicines5030075
- Coelho, J., Montagni, I., Micoulaud-Franchi, J. A., Plancoulaine, S., & Tzourio, C. (2023). Study of the association between cannabis use and sleep disturbances in a large sample of University students. Psychiatry Research, 322, 115096. https://doi.org/10.1016/j.psychres.2023.115096
- Kaul, M., Zee, P. C., & Sahni, A. S. (2021). Effects of Cannabinoids on Sleep and their Therapeutic Potential for Sleep Disorders. Neurotherapeutics: the American Society for Experimental NeuroTherapeutics journal, 18(1), 217–227. https://doi.org/10.1007/s13311-021-01013-w
- Babson, K. A., Sottile, J., & Morabito, D. (2017). Cannabis, Cannabinoids, and Sleep: a Review of the Literature. Current psychiatry reports, 19(4), 23. https://doi.org/10.1007/s11920-017-0775-9
- McPherson, K. L., Tomasi, D. G., Wang, G.-J., Manza, P., & Volkow, N. D. (2021). Cannabis affects cerebellar volume and sleep differently in men and women. Frontiers in Psychiatry, 12. https://doi.org/10.3389/fpsyt.2021.643193
