Lindsey Hudson began to suspect her sleep habits weren’t the norm during her freshman year at Southern Nazarene University in Oklahoma.
A competitive high school cheerleader, teenage Lindsey—busy with daily practices and homework—often wouldn’t go to sleep until sometime between the hours of midnight and 2 a.m., only to wake up bright, early, and surprisingly well rested by 6:30 a.m. in order to do it all over again. (If you don’t have a calculator handy, that’s four and a half to six and a half hours of sleep per night.) Lindsey’s mom, a nurse, adhered to a similarly brief sleep schedule.
“She only ever slept, at most, four to five hours a night,” Lindsey, now 40, recalls. “Anything more than that and something was wrong.”
When Lindsey moved out of her mother’s home and in with her college roommate, Dalene, she started to notice some strange occurrences. Like how Dalene would sleep until noon (or later!) on Saturdays and Sundays. Or how Dalene would take naps most days of the week.
“I never nap,” Lindsey says. “That’s when I realized, Huh, some people sleep a lot more.”
Those differences only became more apparent to Lindsey as her social circle widened. In nursing school, when other students were “dragging” at 6 a.m. clinicals, she felt energized and alert. When she met and married her husband, Brian, it was clear they had vastly different snooze schedules—he preferred to be under the covers by 9 p.m., whereas Lindsey maintained the midnight-ish bedtime she’d had since high school.
“I never nap. That’s when I realized, Huh, some people sleep a lot more.”
That’s not to say Lindsey never dabbled in delayed wakeification. But the side effects weren’t pleasant: “If I sleep more than seven hours, I feel hungover,” she says. “I feel foggy. I feel like I don’t completely wake up.”
Lindsey is what’s known in scientific parlance as a “natural short sleeper,” an individual who thrives on about four to six hours of sleep per night. Experts aren’t sure how many people are true natural short sleepers. As a percentage of the population, they’re likely less than 1 percent. Despite their small numbers, natural short sleepers are elbowing into the conversation around sleep in a big way, calling into question what we’ve long thought we knew about slumber—not to mention the multibillion-dollar sleep industry that’s set on selling us gadgets and gizmos promising more and more and more Z’s! Could these short sleepers’ DNA actually hold the secret to a better night’s rest for us all?
Reassessing Sleep Standards
Google “how much sleep do I need each night?” and you’ll find nearly unanimous answers from the National Institutes of Health (NIH), the Centers for Disease Control and Prevention (CDC), and the American Academy of Sleep Medicine: Seven hours a night is the minimum for adults in order to maintain health and well-being. (The maximum, on the other hand, is a little squishier.)
“The vast majority of adults truly need somewhere between seven and nine hours, and we offer that range because there is a lot of individual difference that we believe is, in part, genetically determined,” says Rebecca Robbins, PhD, a sleep scientist at Brigham and Women’s Hospital in Boston.
Sleep needs diverge along gender lines too. Women require, on average, about 11 minutes more per night than men, according to a study in American Sociological Review. While it’s not entirely clear what’s driving that disparity, women also tend to suffer from higher rates of insomnia than men, largely due to hormonal fluctuations during menstruation, pregnancy, and perimenopause/menopause. Higher rates of anxiety and depression may also play a role. These factors could lead to women needing more time in bed to log the same amount of quality sleep as men.
More Sleep
That phrase “quality sleep” really is key. Focusing on the behaviors that surround sleep—managing stress, not eating too late, relaxing and unwinding close to bedtime—and not just the duration can help optimize our rest periods. “Restorative sleep is waking up and feeling refreshed, almost improved, from your time asleep,” Robbins says.
Restorative sleep is also key for supporting nearly every function and system in the body. Each sleep stage offers its own benefits. During the early, non-REM (rapid eye movement) stages of sleep, for instance, your blood pressure and heart rate are at their lowest, a boon for your cardiovascular health. REM sleep, on the other hand, supports cognitive functions, such as learning and memory. Adequate sleep also supports the production of important building blocks of the body’s immune system and allows the brain to flush out toxins. Yes, you are literally being brain-washed every night!
Individuals who don’t get enough quality sleep can suffer a myriad of short- and long-term consequences: Brain fog and drowsiness from lack of sleep not only make crafting that presentation deck at work more difficult but can actually increase the risk of bodily harm (think: falling asleep at the wheel of a car). Sleep deficiency—defined as not getting enough sleep or getting poor-quality sleep—has also been linked to a number of chronic conditions, including heart disease, stroke, and Alzheimer’s disease. (Interestingly, this doesn’t seem to apply to natural short sleepers, who don’t suffer ill health effects from getting less sleep.)
Despite how much researchers know about sleep today, there’s still so much they don’t know. It’s a notoriously tricky field of research, given the many ways modern life interferes with our natural sleep cycle—everything from the introduction of electric lights into the home to a caffeine-soaked Starbucks on every street corner. Few of us actually let our bodies be our guide when it comes to getting the rest we need. Except, perhaps, natural short sleepers—who are often derided for not following the sleep status quo.
Is Short Sleeping In Our Genes?
Natural short sleepers are those who sleep four to six or so hours per night because that is what feels best for their bodies and brains. If given the opportunity to sleep longer, they wouldn’t want to or need to. Natural short sleepers are not people who’ve trained themselves to snooze for minimal hours in order to be more productive or meet the demands of an unconventional work schedule (such as a night nanny or long-haul trucker).
History is chock-full of men and women who’ve claimed to require very little sleep—Martha Stewart and former PepsiCo CEO Indra Nooyi among them. Thomas Edison, the inventor of the snooze-disrupting lightbulb, famously said he slept just three to four hours a night. “What’s not widely known is that he also had a bed in his office, and he would take extremely long naps of two to four hours at a time,” Robbins says.
And that is one factor that differentiates natural short sleepers from what sleep researchers at the University of California San Francisco call “facultative short sleepers”—those who’ve hacked their sleep schedules because of professional drive or life circumstances. Natural short sleepers rarely, if ever, take naps. They also don’t “catch up” on sleep over the weekend. The hours they log at night are sufficient to keep them alert throughout the day. (Sorry, Thomas.)
Another factor that is more challenging to measure: genetics.
In 2009, a group of researchers discovered the first short-sleep gene. Led by Ying-Hui Fu, PhD, a professor of neurology and a member of the UCSF Weill Institute for Neurosciences, the study found that those with a mutation on the DEC2 gene averaged 6.25 hours of sleep per night while participants without averaged 8.06 hours. This mutation runs in families, which means a mom or dad may carry it and pass it on to one or multiple children. (Though Lindsey has not participated in any studies to confirm she carries the short sleeper gene, the fact that her mother and father were both short sleepers and that her son also appears to be a short sleeper seems to indicate that it likely runs in her family.)
It took one more decade for Fu and study coauthor Louis Ptáček, MD, the John C. Coleman Distinguished Professor in Neurodegenerative Diseases at UCSF, to discover a second and third short-sleep genetic mutation. So far, they’ve published findings on a total of four short-sleep genes, with a few more pending publication.
The mechanism by which these mutations affect a person’s sleep cycle is still largely unknown. In the case of the DEC2 gene, Fu says the mutation leads to an increase in a neuropeptide called orexin, which plays a role in regulating the sleep cycle. More orexin results in more wakefulness. But Fu is convinced there’s much more at play than just orexin. Which means: Yep, more research is necessary.
Despite the various lingering question marks, researchers have identified several traits shared by natural short sleepers. For one, they don’t seem to suffer the ill side effects common among those who are chronically sleep-deprived (i.e., their health isn’t negatively affected by notching less sleep). And that is notable! It means that the seven-hour standard may, in fact, not be the minimum for all adults to stay healthy and happy.
Additionally, natural short sleepers don’t tend to experience jet lag, they have higher pain tolerances, and there is even anecdotal evidence that they may live longer. Dr. Ptáček notes that many of the natural short sleepers he’s aware of have lived into their 70s, 80s, or 90s and are in good health. Fu hypothesizes that natural short sleepers are meeting their bodies’ needs while sleeping more efficiently.
As a quasi-test of this idea, the researchers crossbred mice with genes predisposing them to Alzheimer’s disease and mice with natural short sleeper genes. Sleep deprivation tends to exacerbate Alzheimer’s in mice. But in short sleeper hybrid mice, there was a slower accumulation of the abnormal proteins associated with Alzheimer’s, suggesting that the natural short sleeper gene was protective. “While this doesn’t prove that natural short sleepers live longer, it does support the notion that natural short sleeper mutations lead to sleep in these people where they are able to accomplish some physiological processes—waste clearance, perhaps—more efficiently,” Dr. Ptáček says.
The researchers used mouse models to validate their overall findings as well, employing mice bred with the same short sleeper genetic mutations they discovered. The result? The mutated mice slept less than their unmutated rodent peers. “Mice don’t have to go to work or go to school,” Fu says. “They can sleep anytime they want, but they don’t sleep any more.”
Fu and Dr. Ptáček admit that their findings are controversial in the field of sleep research. Despite what they’ve uncovered, many in the medical community still dismiss the phenomenon of natural short sleepers.
Lindsey, now a nurse practitioner, says that her own primary care providers typically don’t believe her when she says she needs just five or six hours of sleep a night, reiterating that the literature recommends seven to eight hours. Ultimately, they don’t say much else beyond that since they know she’s a nurse and it’s a bit of a losing battle with her.
What It’s Really Like To Be A Short Sleeper
If you were to pull into the parking lot of Jewel-Osco in the Chicago suburb of Round Lake at around 6:30 a.m. on a random weekday and peer through the grocery store’s large front windows, you’d likely spy one or two cashiers, maybe a bakery department employee icing the day’s maple bars.
There’s a good chance you’d also see a lone shopper, 77-year-old Joanne Osmond, pushing her cart through the aisles, making small talk with the staff. After all, what else is there to do at 6:30 a.m. when you’ve been awake for hours?
Joanne is a confirmed natural short sleeper—one of the dozens of participants in Fu and Dr. Ptáček’s studies. Like Lindsey, she didn’t realize her nocturnal routine was unusual until she went off to college. Joanne’s dad and several of her siblings were also natural short sleepers. Her mom was the oddball who needed a full night’s rest.
“We did not wake my mom up,” Joanne says. “She was as grumpy as could be.” To ensure their mom remained undisturbed, Joanne and her siblings stayed in their rooms until what was deemed an appropriate hour to get up. This was long before iPads, or even TVs, were the norm, so they’d pass the predawn hours reading any and every book series they could get their hands on at the local library—Nancy Drew, the Hardy Boys, the Bobbsey Twins.
As Joanne got older and married a non-short sleeper, reading remained her companion. She and her husband, Bud, would climb into bed together at night; he would fall asleep right away; she would stay up until 11 p.m. or midnight. Joanne was then the first to rise—usually around 3:30 or 4 a.m.
The years wore on, and Joanne, who works as an online instructor with half of her students in another time zone, began to expand her late-night to-dos. Today, she might grade papers or help students across the country. She is the picture of productivity. You can sense something akin to a restless energy when speaking to her, and those extra hours have surely allowed her time to reach her many goals. Throughout her life, Joanne has managed to find and befriend other short sleepers in her local community, and they’ve often stayed up late working on projects together. This fellowship has been vital for her. Sure, being awake some 20 hours a day has created opportunities for achievement, but it’s also resulted in, at times, a profound sense of isolation.
How To Sleep Better Tonight
“Being a short sleeper is extremely lonely, because even though there were people all around—my husband, my children—I couldn’t wake them up if I wanted to talk to them. They had to sleep,” Joanne says. “Here I was with all these ideas and things I wanted to do and places I wanted to go, and I was restricted because everybody else was sleeping.”
Even her early-morning shopping runs are tinged with a hint of melancholy. “It’s really dark out, and most people aren’t up yet,” she says. “I drive out and all the lights are off. It makes you feel like you’re totally alone.”
Here, too, she’s endeavored to foster connection and community. “I know everybody at the Jewel-Osco and say good morning,” Joanne says. “One of the employees owns a wonderful Polish restaurant, Reflections on Deep Lake, so I invited two friends to dinner there one evening. The woman who checks me out lost her mother recently, so I gave her a card. We are family!”
Understanding Keys For Better Sleep for All
For Lindsey, who considers herself more of an introvert, there have been few downsides to her short sleeper status. Working 12-hour shifts in telehealth, she finds that the extra wakeful hours allow her to decompress after a long day of caring for patients and tending to her two children.
“It is my sanity,” Lindsey says of her evening alone time. She’ll usually read dark romances or catch up on TV her husband doesn’t watch, like the Max medical series The Pitt or any variety of Hallmark movies. Lindsey admits she did once run into a bit of trouble when she “stream cheated” one night, watching an episode of Netflix’s Too Hot to Handle, a show the couple usually enjoy together.
“My husband was like, ‘You caught up on it without me? We were supposed to watch that together!’ ” she recalls. “I’ve learned not to do that, because he takes it personally.”
Reality TV drama aside, there’s not much Lindsey would change about her sleep situation. “I don’t have a problem falling asleep, and I stay asleep,” she says.
If only we could all be so lucky. An estimated 35 percent of Americans get insufficient sleep, according to the CDC. And it’s that concern that Fu and Dr. Ptáček ultimately hope to remedy with their research into natural short sleepers. “If we all can get a good night’s sleep, then we can prevent many of the diseases of aging,” Fu says.
Understanding the underlying biology of sleep—a mystery that researchers are still working to unravel—could lead to advances that would help people suffering from insomnia and other sleep disorders. “There is hope that we might be able to develop a medication that can work in a way that doesn’t cause problems or side effects, but rather improves the quality of sleep and the efficiency of sleep,” Dr. Ptáček explains.
Bottom line, says Fu: “The goal is to help everybody to get the best sleep they can,” whether that’s four hours, six hours, or eight hours. We can all raise a mug of Sleepytime Tea to that.
How To Optimize Your Slumber With Insights From Short Sleepers…
1. Respect your body’s rhythms.
Being highly attuned to sleep demands is a quality of natural short sleepers. And given the wide range of possible requirements (as little as 4 hours a night for some natural short sleepers and as much as 12 for some natural long sleepers, says Dr. Ptáček), honoring your own needs—rather than following one-size-fits-all advice—will go a long way toward ensuring you get the most out of your time under the covers.
2. Prioritize rest as you would other health habits.
Natural short sleepers don’t shape their sleep schedules around their lifestyles; rather, they shape their lifestyles around their sleep schedules. “Everyone has some control over their sleep,” Fu says. “Just as many people prioritize exercise to stay healthy, one can choose to prioritize sufficient and quality sleep to support their long-term health.” Think of sleep and your next pilates class as a one-two punch for longevity.
3. Maybe lay off the caffeine?
We know, we know—you’ve heard this advice before. But hear us out! Another interesting fact about Joanne, the research-confirmed natural short sleeper, is that she doesn’t drink coffee. Mostly because she doesn’t need it to stay awake (hello, adequate sleep). Caffeine consumption can create a never-ending cycle of reduced sleep quality, studies show, so if you’re not feeling well rested, that pistachio latte might be to blame. And how can you know how much sleep your body really needs if you’re always self-medicating your insomnia with energy drinks? Time to find out.
Amy Wilkinson is a contributing entertainment editor at Women’s Health, where she edits the magazine’s celebrity cover stories and writes health features. She has previously held editor titles at Entertainment Weekly and MTV News. In 2021, Amy completed her 600-hour teacher-training at Core Pilates NYC to become a comprehensively trained Pilates instructor.