How marijuana and alcohol affect my sleep

A few nights ago, I used marijuana for the first time after abstaining for several months. The following morning, I noticed that my overnight resting heart rate (RHR), as measured by my Oura ring, was ~8 BPM lower than the previous few nights, and my heart rate variability (HRV) was also ~10 ms higher than typical for me. Did using marijuana actually positively impact my sleep? I dig into my data in this post.

Outline#

1. Data acquisition
2. How marijuana and alcohol affect my resting heart rate and heart rate variability
3. How marijuana affects sleep staging
4. Marijuana usage habits
5. Alcohol usage habits
6. Conclusions

Data acquisition#

The data was collected from December 23, 2021 to December 31, 2024, covering a time span of just over 3 years. In this time frame, there 70 days where I consumed alcohol, 377 days where I consumed marijuana, 610 days where I consumed no substances, and 0 days where I consumed both alcohol and marijuana. There are 48 days in this interval where no biometric data was collected, so they are omitted. I use Binders to log my marijuana and alcohol usage along with the Oura ring to calculate my biometric data. I processed the data using Python.

How marijuana and alcohol affect my resting heart rate and heart rate variability#

In Figure 1, I show my resting heart rate and heart rate variability as measured by my Oura ring on nights where I consumed alcohol (top right), consumed marijuana (bottom left), and when I consumed no substances (bottom right). I never consume both marijuana and alcohol together (top left). Figure 2 also shows this data plotted together on the same axes.

From these figures, it’s clear that consuming alcohol negatively impacts my heart—my RHR is generally increased and my HRV is generally decreased as compared to nights where I consume no substances. Interestingly, when consuming marijuana, on average, my RHR slightly decreases and my HRV slightly increases when compared to nights where I consume no substances. The harmful tail of the distribution is dominated by nights where I consume alcohol (high RHR and low HRV) and the beneficial tail of the distribution is dominated by nights where I consume marijuana (low RHR and high HRV).

How marijuana affects sleep staging#

I was also interested in seeing how marijuana impacts my sleep staging. First, for reference sake, in Figure 3 I look at the time of day that I fall asleep (blue) and the time of day that I wake up (orange) for the data in this study.

Because I have much more data from when I consume marijuana (377 samples) than alcohol (70 samples), I only look at sleep staging on nights where I consume marijuana (377 samples) and compare it to when I consume no substances (610 samples). It is important to note that I have nearly double the amount of samples when using no substances when compared to when using marijuana and that is visible in the following several figures.

Figure 4 shows a histogram of how many minutes per night I spend in light sleep for nights when I consume marijuana (purple) and nights where I consume no substances (pink). Orange indicates the overlap of these two distributions. From this, it appears that marijuana generally decreases the amount of time I spend in light sleep.

Figure 5 shows a histogram of how many minutes per night I spend in deep sleep for nights when I consume marijuana (purple) and nights where I consume no substances (pink). Orange indicates the overlap of these two distributions. From this, it appears that marijuana readily increases the amount of time I spend in deep sleep. When using marijuana, the distribution of deep sleep has a higher mean and higher standard deviation. Without marijuana, the distribtion of deep sleep has a lower mean, lower standard deviation, but higher skewness as compared with using marijuana.

Figure 6 shows a histogram of how many minutes per night I spend in REM sleep for nights when I consume marijuana (purple) and nights where I consume no substances (pink). Orange indicates the overlap of these two distributions. Studies have shown that using marijuana typically decreases the amount of REM sleep one has¹, and from this it appears that marijuana, on average, slightly decreases the amount of time I spend in REM sleep, but the difference is slight.

Finally, I looked at my total sleep on nights when using marijuana compared with no substances in Figure 7. It seems as though I spend slightly more time sleeping when consuming marijuana when compared to consuming no substances, although the difference is slight.

For completeness sake, I also looked at sleep latency and time in bed, although they weren’t too insightful.

Marijuana usage habits#

In analyzing this data, I think it’s important to report how I consume marijuana, which I will cover in this section. Figure 8 shows the time of day that I use marijuana. From this, it’s clear that I typically use marijuana in the evening hours after work ends and before bed. A funny observation in the data is that there’s a large spike where I consume marijuana at 5 PM which is due to me considering 5 PM as the start of the end of the day.

Figure 9 shows the number of times in a day that I use marijuana on days that I do use marijuana. I mostly would use once a day, sometimes twice a day, and rarely more than twice a day.

Figure 10 shows the methods I used to consume marijuana and their frequencies. My favorite method was using a dry herb vape, which heats small amounts of dried marijuana into a vapor to be inhaled. I also used edibles occasionally, although since their effects lasted longer than vaping I typically only used edibles on weekends.

Alcohol usage habits#

Finally, I look at my alcohol usage habits for the data in this data set. I strongly prefer marijuana over alcohol, so I use alcohol much less often. Figure 11 shows the time of day that I consume alcohol, which is once again typically in the evenings.

Figure 12 shows the number of times I consume alcohol on days that I do consume alcohol. When I do drink, I’ll typically have 2-3 drinks, although I do consume more than 3 drinks fairly often.

Figure 13 shows the types of alcoholic drink I consume and their frequencies. I don’t really have a favorite drink, although in general I enjoy drier red wine. “Can” here refers to a canned drink that doesn’t fit neatly into the other categories, such as hard lemonade or a canned cocktail.

Conclusions#

The data presented in this post highlights clear differences in how marijuana and alcohol consumption impact my biometric data and sleep patterns. For me, alcohol use is associated with an increase in resting heart rate (RHR) and a decrease in heart rate variability (HRV), indicating potential cardiovascular stress. In contrast, marijuana use appears to slightly decrease RHR and increase HRV, suggesting a more relaxed physiological state.

Analysis of sleep staging reveals that marijuana consumption decreases light sleep and increases deep sleep duration. In alignment with the academic literature, the amount of time I spend in REM sleep, on average, slightly decreases when marijuana¹. Total sleep time is also slightly higher on nights when I consume marijuana, though the effect is modest. By far, the most pronounced effect of marijuana on my sleep staging is that in increases the amount of time I spend in deep sleep, with a clear separation in the distributions of deep sleep duration between nights when I consume marijuana and nights when I abstain from substances.

I do not wish to make any claims stating that marijuana definitively improves my sleep quality, but it seems as though it may have, albeit only slightly. Using marijuana, on average, reduces my RHR, increases my HRV, and increases the amount of time I spend in deep sleep, all of which are, at least on the surface level, beneficial. Finally, it’s worth noting that there are other compounding variables that likely affect this data, such as the fact that my underlying stress level regardless of marijuana and alcohol consumption cannot be untangled from the data, and the fact that Oura ring changed their sleep staging algorithm during this experiment. Additionally, I believe it is important to note that I no longer consume marijuana primarily due to the fact that I am drug tested for my employment.

Please let me know if you have any comments, questions, or suggestions.

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1. Relevant studies about how marijuana affects sleep include The effects of cannabinoid administration on sleep: a systematic review of human studies., Effects of high dosage delta-9-tetrahydrocannabinol on sleep patterns in man and Effects of marijuana extract and tetrahydrocannabinol on electroencephalographic sleep patterns . ↩︎