Does Cannabis Affect Your Sleep?

Cannabis use has become increasingly popular since many states began legalizing the drug for recreational use and sale. Between 2021 and 2022, sales of marijuana increased 32%, according to Fortune. Of course, the pandemic may have driven this increase with everyone staying home, explains U.S. News and World Report. Currently, 38 states have legalized marijuana for medical use and 19 states have legalized marijuana for recreational use, explains CNET.

The reasons why someone may smoke marijuana are varied. However, there is one potential benefit that many people turn to marijuana for, and that's better quality of sleep. It's estimated that about 70% of young adults who use marijuana say they do so to improve sleep, with 85% of those who use medical marijuana saying it improves their sleep quality, according to a 2014 study published in the journal Current Addiction Reports. But what does science say? Can cannabis play a role in your sleep?

Sleep is extremely important for the body. There is a reason why every mammal on the planet gets some amount of sleep, according to the Sleep Foundation. The benefits of getting enough sleep include boosting your immune system, maintaining your weight, reducing stress, and improving your mood, according to the Office of Disease Prevention and Health Promotion. Anything that disrupts your sleep can be detrimental to your health.

When you go to bed, you go through four stages of sleep multiple times throughout the night. Stage one is falling asleep, which takes anywhere from five to 15 minutes, on average. Stage two, or light sleep, is when your heart rate begins to slow and your body temperature drops. Stage three is when your muscles relax and the deepest sleep takes place. Finally, rapid eye movement (REM) sleep is the stage when dreams occur and the brain becomes more active, per Verywell Health. 

How does cannabis come into the picture in regards to sleep? The reason marijuana can make you sleepy is that cannabinoids (the chemicals found in cannabis, like THC and CBD) connect to receptors in the brain after you smoke. They send signals to increase the levels of adenosine, promoting sleep, according to the Sleep Foundation. For people with chronic illnesses, such as insomnia, anxiety, or pain, this can be helpful.

However, cannabis can interrupt REM sleep, which helps with learning, memory, and brain development, according to MedicalNewsToday. According to a 2021 study from the journal Regional Anesthesia & Pain Medicine, consistent marijuana smokers — defined as people who smoked 20 or more days per month — were less likely to get the recommended amount of sleep due to interruptions in their REM cycles. People with conditions, such as post-traumatic stress disorder, can potentially fall asleep easier and wake up less during the night by using marijuana before bed (per the Sleep Foundation).