Cannabis may make sleep worse, study says

People who used marijuana more regularly reported sleeping either too little or too much

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People who use cannabis regularly are more likely to have poorer quality sleep, a new study has found.

Contrary to the popular belief that marijuana helps with falling and staying asleep, scientists found that using the psychoactive drug may result in disrupted sleep.

A study that analysed the sleep duration of adults who used cannabis at varying frequencies found that those who used it more regularly were more likely to experience sleep that was either too long or too short.

People who used cannabis for 20 or more days in a 30-day period were 64 per cent more likely to sleep fewer than six hours a night and 76 per cent more likely to sleep longer than nine hours a night, researchers found.

Those who practiced moderate consumption of cannabis (fewer than 20 days) did not experience shorter sleep, but were 47 per cent more likely to sleep nine or more hours a night.

The study also found that people who used marijuana within the last 30 days were more likely to report difficulties in falling asleep or staying asleep, as well as being more likely to have talked about sleep problems with a health care provider.

According to scientists, the optimal sleep duration is between six to nine hours a night.

The study examined the use of cannabis to aid sleep among 21,729 adults between the ages of 20 and 59, using data gathered by the National Health and Nutrition Examination Survey.

Study author Calvin Diep, a resident in the department of anaesthesiology and pain medication at the University of Toronto, told CNN that long and short sleep durations have been associated with health problems such as increased risk of heart attacks and strokes.

“It seems with sleep there’s kind of this ‘Goldilocks phenomenon’ where there’s an amount that’s ‘just right’,” he said.

However, Diep said that whether or not cannabis was the cause of people’s sleep problems was inconclusive, adding: “We can’t know for sure whether this was simply individuals who were having difficulty sleeping, and that’s why they use the cannabis, or the cannabis caused it.”

Other studies have suggested that using cannabis regularly may result in users building up a tolerance to the drug’s initial sleep-inducing effects.

Research published in the BMJ Supportive and Palliative Care journal last year suggested that, in the long-term, medical cannabis may not ease sleep problems in people with chronic pain.

The observational study found that patients who used medical cannabis more frequently reported greater difficulty falling asleep and more frequent waking during the night.

The researchers, from the University of Haifa and Rambam Hospital in Israel, said this could “signal the development of tolerance” to the drug.