What everyone is seeing here is a combination of cannabis experiences
, let me explain.
OP, cannabis is generally known to impair REM sleep so it typically causes a disruption in deep sleep. However high dose THC can lead to people falling asleep. So cannabis can help people fall asleep but it's a worse sleep.
Impaired REM sleep has been studied a lot as other things also cause it, and they've also found there's REM rebound in sleep when the cause is removed.
This is neuronal stuff, so it takes ~4 weeks to reset the body (with a complete break). Any less than a complete break will take longer than 4 weeks to reset.
Also note that significant users of cannabis / THC will develop a tolerance to it (e.g. daily), and that will lessen REM sleep impairment. This is the human body adjusting to the cannabis / THC exposure & adjusting itself to compensate (receptor down regulation) and move to a more typical homeostatic body regulation. There still will be REM sleep impairment but it won't be noticeable to most significant users until they take a 4 week or so cannabis / THC break. Low tolerance cannabis / THC users have significant REM sleep impairment & easily identify it. I'm a microdoser who only vapes a few times on weekends & I get big swings in REM sleep. I can green out as well if I'm not careful, so cannabis has helped me go to sleep as well
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Even more to add, there's also the known phenomenon of variable population level responses (standard normal curve stuff). What that means is that some people are more naturally susceptible to cannabis / THC, while some are not as naturally susceptible to it. This means that some people will have less REM impairment than most others, while some others will have more REM impairment than most others.
With everything described all going on out there, it's surprising to see& a range of experiences within the realm of REM impairment & sleep quality w/ cannabis.
Hope that helps.
HAF so sorry for any spelling / grammar issues