Can binge-watching harm your sleep?

How does watching all those Netflix series affect your sleep quality? New research investigates.

The phenomenon of binge-watching has made an appearance in very recent years with the advent of streaming services such as Netflix and Amazon Prime. It is currently estimated that 71 percent of the adult population of the United States watches video content online.

As opposed to conventional TV, online and on-demand access to our favorite shows makes it easy to watch a high number of episodes in one sitting, usually in the evenings.

But what is the cost of such intense media consumption on our sleeping habits? Researchers from the University of Michigan in Ann Arbor, in collaboration with the Leuven School for Mass Communication Research in Belgium, set out to investigate.

The first author of the study is Liese Exelmans, a researcher at the Leuven School for Mass Communication Research, and the findings were published in the Journal of Clinical Sleep Medicine.

The link between binge-viewing and sleep

Exelmans and colleagues conducted a survey in 423 young adults aged between 18 and 25, 61.9 percent of whom were female. The participants filled in an online questionnaire that assessed how often they watched TV and how often they binge-watched.

They answered questions about the quality of their sleep using a standard questionnaire called the "Pittsburgh Sleep Quality Index." The researchers also assessed whether or not they had fatigue using the Fatigue Assessment Scale, which is another standard instrument used to assess chronic fatigue in adults.

Also, to assess insomnia, the researchers used the Bergen Insomnia Scale - that is, a tool devised in 2008 for assessing "sleep onset, maintenance, and early morning wakening insomnia." Finally, cognitive and somatic arousal before going to sleep was assessed using the Pre-Sleep Arousal Scale.

The researchers applied regression analyses to the data obtained, and a mediation analysis was performed in an attempt to identify a mechanism that may explain any potential associations.

Binge-viewing increases fatigue, insomnia

Of the entire sample studied, over 80 percent identified themselves as binge-viewers. Of these, more than 20 percent had engaged in binge-viewing at least a few times per week in the month prior to the study.

Overall, men binge-watched significantly less than women - however, when they did engage in binge-watching, their sessions were nearly twice as long as those identified among women.

Almost a third of those who reported poor sleep (32.6 percent) "had a poor sleep quality associated with being a binge-viewer." Those who binge-watched, in other words, reported significantly more fatigue and insomnia than those who did not.

The study found that "[h]igher binge-viewing frequency was associated with a poorer sleep quality, increased fatigue, and more symptoms of insomnia, while regular television viewing was not."

Additionally, "Cognitive pre-sleep arousal fully mediated these relationships," the researchers write, suggesting that being kept mentally alert may be the reason why binge-watching has such a negative effect on sleep.

The study's lead author spoke to Medical NewsToday about the significance of the study.

"[It] turned out that regular TV viewing was not related to sleep, but binge-watching was. This illustrates how important it is to stay on top of new ways of technology use and how they might affect our sleep behavior. In addition, we have exposed a mechanism: cognitive arousal.

Liese Exelmans

"[This] is important," she adds. "[So] far, there is a good amount of research documenting the effects, but we know little about "why" or "how" the effects manifest. This is one part of the answer."

"Bingeable TV shows have plots that keep the viewer tied to the screen," explains Exelmans. "We think [viewers] become intensely involved with the content, and may keep thinking about it when they want to go to sleep."

Exelmans also spoke to us about the limited resource that is self-control and how that plays into the results found.

"Binge watching is also a self-control issue: we cannot manage to stop. Self-control is something we use throughout the day, but we have little self-control around bedtime (we've been "good" all day long, and people may feel they deserve a little reward for that). This feeling is very familiar to many, and often is associated with a little more me-time before bed, relaxing with our tech."

Some of the limitations to the study, the author said, include the "self-reports [and the] cross-sectional study (we cannot determine causality, but can only say that those who report a higher frequency of binge-watching also reported poorer sleep)."