A Hidden Effect of Marijuana Use

Marijuana's impact on the sleep cycle can produce both acute and chronic effects on a person's functioning.Researchers have demonstrated that THC ingestion decreases SWS and REM sleep, and has sometimes been found to eliminate REM sleep altogether in rats, rabbits, and cats. In later research, the same effect was observed in humans in controlled studies, with the added finding that sleep cycles did not return to normal until after about one week of abstinence.