From a cursory review of this week's news, someone might reasonably believe that a new, landmark study has shown — with certainty — that women need more sleep than men because of hard-wired differences between the male and female brains. Social media feeds are littered with headlines to that effect. But here's the thing: There is no new study and we don't know if the claim is true.
Sometimes, the virtual voyage of aggregated science content resembles a game of telephone, in which bad service muddles a message that doesn't merit transmission in the first place. In the end, we're left with a mess of posts and "Science Says!" must-reads that are a pale facsimile of the original items. The above-mentioned coverage of women's heightened rest requirements, currently making the e-rounds, exemplifies the process by which bunk non-news becomes big news.
The "Original" Article
On March 11, 2016, Metro, a UK news aggregation site, published a short article called "Women actually need more sleep than men so let's all go back to bed." It was immediately picked up by numerous outlets and started trending on Facebook. According to Crowdtangle, a service that tracks online engagement, the study is the subject of 12 of the 34 most over-performing sleep-related posts on Facebook in the last week. Yet the original article doesn't reference any specific research — new, old or prospective — to back up the headline. Instead, the scientific authority for the article's claim rests on aggregated quotes from Jim Horne, a respected sleep doctor and director of Loughborough University’s Sleep Research Centre. Here are a few choice nuggets:
"Women’s brains are wired differently from men’s and are more complex, so their sleep need will be slightly greater."
"Women tend to multi-task – they do lots at once and are flexible – and so they use more of their actual brain than men do...Because of that, their sleep need is greater." (Writer's note: "Greater sleep need" does not necessarily mean duration, here.)
Spend a few more minutes trying to make sense of and trace back the quotes, and it becomes apparent that the quotes don't refer to recent developments in sleep research or any new study.
The article didn't indicate that most of Horne's quotes actually date back to a 2010 Daily Mail story. And, at least one quote attributed to Horne appears to belong to Edward Suarez at Duke University.
Professor Jim Horne, director of Loughborough University’s Sleep Research Centre, said that "for women, poor sleep is strongly associated with high levels of psychological distress and greater feelings of hostility, depression, and anger...In contrast, these feelings were not associated with the same degree of sleep disruption in men."
Suarez provided the quote in a press release for a 2008 study he co-authored. From the release, reprinted by Science Daily:
"We found that for women, poor sleep is strongly associated with high levels of psychological distress, and greater feelings of hostility, depression and anger. In contrast, these feelings were not associated with the same degree of sleep disruption in men," says Suarez.
We reached out to Metro for comment and will update the story if they respond.
For all intents and purposes, the Duke study is the "new study" in question – but no outlet, to our knowledge, has acknowledged the work they're inadverdently reporting on. The Duke research was also the "new study" in 2013, when the then-five-year-old research garnered a flurry of press, much of which incorporated Horne's 2010 quotes to buff up the delayed coverage. It's hard to know which outlets, if any, were or are cognizant of which piece of research they're writing about or when it actually counted as "news."
At some point, the collective content factory lost track.
The Snowball Effect
Through aggregation, Horne's floating Metro quotes blossomed into a full-fledged, new study. And, that "study" started rolling.
Over at Distractify:
Us Weekly, linking back to Metro, reported: "Sleep in the name of science! Women need more Zzz’s than men because their brains are more complex, a new study from England’s Loughborough University reveals."
"News.com is reporting a new study has come out that says you ladies need more sleep than the dudes," reported a local radio station website. "A study from Loughborough University’s Sleep Research Centre in England say women need more sleep than men because their brains are more complex."
What Studies Do Say
There is research — though not enough — on the differences between male and female sleeping habits, and the biological, behavioral and cultural factors informing those differences. A 2014 review paper, published in the Journal of Women's Health, listed a number of research-backed differences — here are a few:
1. Across normal (non-disordered) sleepers in the general population, sex differences exist in sleep quality, duration, latency and architecture. Women take longer to fall asleep, report more sleepiness (for the 55-and-under crowd), and differ in the amount of time spent in the four N-REM sleep stages.
2. Sleeping disorders also afflict men and women differently, both in prevalence and in presentation of symptoms: Women have a 40-percent higher risk than men for insomnia, whereas men are twice as likely to develop Obstructive Sleep Apnea.
3. Women metabolize Zolpidem (generic Ambien) twice as slowly as men.
Studies on the distinctions between male and female sleep often implicate reproductive hormones, anxiety and other mood disorders, and the ways in which men and women report symptoms of sleep disorders. Actually, the past few years have seen more exploratory work on the role of sex hormones in the development of brain circuits (including the orexin system) that regulate sleep-wake patterns.
It's hard to find strong evidence that women are wired to need more sleep than men. And, in fact, Horne never uttered those words.
"I never said that women actually need more sleep, they just tend to take more sleep," Horne told Van Winkle's. "We have not undertaken a new study."
Here, in Horne's own words, is an explanation of his research:
"Women tend to sleep for around 15 minutes longer than do men, which is more apparent in those younger than 45 years of age, and has been reported in a variety of studies, including ours, as well as from UK National Statistics. This is not because of myths relating to ‘more delicate constitutions’, but may well be due to women having more deep or slow wave sleep (SWS), and a sign of their having greater brain (ie. cortical) recovery during sleep. Which in turn indicates that women tend to work their cerebral cortices harder than does the age-related man. Women seem to multi-task to a greater extent than do men, which requires dealing with information from different sources and senses, then selecting which piece of information to attend to and what to ignore, including having quickly to decide on actions and priorities; all of which are cortically demanding and create much ‘brainwork’ than, say, reading, completing a crossword, or undertaking tasks sequentially during the day, or having all one’s attention focused on a computer screen. Coincidentally or otherwise, maybe owing to a greater degree of ‘use it or lose it,' and that women happen to retain more SWS with age, the female cortex also ages more slowly than that of men, by about 5 years. So, by the healthy age of 75, the cognitive ability of the female brain is comparable with that of a 70 year old man."
Delayed news coverage depicted the 2008 Duke study as proving the more-Zzzs-for-females theory, but it's not clear the study's findings actually support that conclusion, let alone prove it. The Duke team found that women suffer certain health effects of sleep deprivation more acutely and severely than men do. But, the fact that one group is more affected by sleep loss than another doesn't necessarily mean the members of the first group need to log more shuteye each night.
Arguing for any definitive causal link between the negative impact of sleep loss and the need for longer sleep duration relies on a considerable leap in logic. Most coverage of the Duke study glossed over this leap. Shape magazine, to its credit, pointed out the stumble:
And while you may have seen recent headlines proclaiming that women need more sleep than men, the truth is a lot more complicated, says Aric Prather, Ph.D., an assistant psychiatry professor at UCSF... "I don’t think there is any good evidence yet that women need more sleep than men," Prather says. "The present data is more in support of the fact that women may be more susceptible to the negative effects of poor sleep quality.
In the end, nothing bad will happen to readers who now incorrectly believe that some brand-new study proves women need more nightly sack-time than men. But, the way this "new study" went gangbusters highlights how quickly and significantly science coverage can devolve in the hands of hasty, headline-driven aggregation. Here, we have a case study in the absurdity that percolates when we — because aren't we all a little guilty of this? — indiscriminately throw up OMG news-nuggets to reserve our space in the conversation. We could collectively benefit from being more careful and giving up our attachment to the "proof" and "confirmation" that rarely exists, even when science really says something.