New study links nightmares with too much sleep

A new study has uncovered a link between nightmares and too much sleep.

According to Quartz, "...researchers from the University of Oxford found that those reporting more than nine hours of sleep a night were 40% more likely to have nightmares than those who...slept for shorter amounts of time."

One of the paper's authors, Stephanie Rek, has indicated that this may be caused by an extended amount of REM sleep—a phase where the brain is active and dreaming typically takes place.

The study involved 846 U.K. participants who filled out an online survey about the frequency and severity of their nightmares in addition to other factors like sleep duration, stressful life events, and symptoms of PTSD, or post-traumatic stress disorder.

Based on the team's assessment, some of the lifestyle behaviors like alcohol did not appear to have an influence on bad dreams.

However, sleep duration did, as did other variables like worry, hallucinatory experiences, and paranoia. As such, Rek has said that therapy may be able to help in some cases but more research would be needed.

Stress has also been cited by the National Sleep Foundation as a common contributor to nightmares in addition to eating before bed, medications, and sleep disorders.

Ironically, the foundation also lists lack of sleep as a potential cause and recommends that people keep their rooms cool and wind down at night to increase sleep time.

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