By Study Finds Cannabis Use Linked to Poorer Measured Sleep
Millions of Americans use cannabis products as sleep aids, but a new Northwestern Medicine study suggests marijuana may not improve sleep the way many people believe it does. The study found both lifetime and recent cannabis use were associated with poorer objectively measured sleep quality, even though participants generally did not perceive their sleep to be worse.
The study is published in JAMA Network Open. “This study challenges the common belief that cannabis helps people sleep better,” said corresponding author Dr. Thanh-Huyen T. Vu, research associate professor of preventive medicine (epidemiology) at Northwestern University Feinberg School of Medicine.
The scientists followed participants from young adulthood into middle age for nearly 35 years, repeatedly tracking their cannabis use over time. In middle age, participants wore a wrist-based sleep monitor for a week and completed sleep surveys, allowing the scientists to compare objective measures of sleep with participants’ own perceptions of how well they slept.
Users Did Not Notice Their Own Sleep Disruption
The study found both long-term and recent cannabis use were associated with poorer sleep quality when the wrist-worn monitoring device objectively measured participants’ sleep. However, participants who used cannabis generally did not report sleeping worse than people who didn’t use it.
When researchers asked participants to rate their own sleep quality, cannabis use showed no association with whether people felt they slept well or poorly. The findings suggest cannabis-related sleep disruptions may go unnoticed by users themselves, the study authors said.
Study Details
The research drew on decades of repeated cannabis use tracking, with sleep measured objectively through a wrist-worn device and subjectively through participant surveys in middle age. The comparison of these two types of measurement was central to the findings.
The research team plans continued work on the relationship between cannabis use and sleep.
