If the weed Twitterverse is to be believed, a lot of marijuana users rely on a nightly puff or two to drift off into la-la land.

And surveys of marijuana users show they do indeed rely on the drug for better sleep.

Unfortunately, science isn’t quite as convinced about the positive effects of cannabis on our ability to catch some Z’s. Research since the 1970s has shown mixed results on weed’s sleep-aiding benefits. A 2018 randomized, double-blind, placebo-controlled study — the gold standard — found no benefit from CBD on sleep in healthy volunteers. Other studies have also found high rates of insomnia when withdrawing from nightly use.

“We know from studies of recreational users of cannabis that sleep disturbances are common when they are attempting to quit cannabis use,” said sleep psychiatrist and neurologist Dr. Bhanuprakash Kolla, who works in the Center for Sleep Medicine and the Division of Addiction Medicine at the Mayo Clinic in Rochester, Minnesota.

“Up to two-thirds of them report sleep disturbances when they stop cannabis use, and it is a frequent reason for relapse to cannabis use,” Kolla said. “Therefore, cannabis can set up a pattern where it is minimally helpful for sleep in the short term and then disrupt sleep, making it difficult to stop use in the medium to long term.” [Read more at CNN]