By Dr. Mercola
One in five Americans now owns a wearable, health-tracking device. One in ten wear them daily.1 The devices, such as Jawbone's UP, provide something that has never before been available on this scale – actual sleep data (and more) from up to 1 million wristband users.
Withings, a maker of health-tracking devices, is the latest to record and analyze such data to give a picture of sleep in America. They recorded 15 million nights of sleep from more than 10,000 device users last year.
Although many of Withings device users are men between the ages of 35 and 40 who are interested in technology, the company states its users vary across genders, geography and age. As such, their sleep data may apply to Americans as a whole.
How Much Sleep Is the Average Person Getting a Night?
Withings' data revealed the average device user is sleeping seven hours and 50 minutes each night, or nearly eight hours.2 This is surprising, since other data suggests Americans are far more sleep deprived.
For instance, according to the documentary Sleepless in America, 40 percent of Americans are sleep deprived, with many getting less than five hours of sleep per night. It could be that users of fitness-tracking devices are more health conscious than the general population, hence the longer sleep hours at night.
According to Withings' data, the average American falls asleep at 11:32 pm and wakes up at 7:22 am, although there were variations according to state. For instance, New Yorkers tend to go to sleep later, at 11:54 pm, and rise later, at 7:36 am, than people in other states.
Coloradans tend to be early risers, waking at 7:07 am, while those in the Midwest tended to go to sleep earlier. Overall, Montanans are getting the most sleep, at eight hours and 20 minutes a night. Other good sleep states include South Dakota, Wyoming, and Maine.
Delaware residents came in as the shortest sleepers at seven hours and 36 minutes a night, followed closely by residents of Rhode Island, New York, Massachusetts, and Washington, D.C. If you want to find out where you fall on this curve, check out the TIME Labs sleep calculator.3
Fitness Tracker Data Also Revealed Most Sleep-Deprived Cities
Jawbone impressively collected data from 1 million UP users (I was one of them) in 2014, revealing a "year in sleep." Among the information was data for tens of thousands of Americans in 21 US cities, which revealed the most sleep-deprived areas.
What they found was that sleep times were remarkably similar, ranging from a low of 6.82 hours in Houston, Texas to a high of 6.93 hours in Orlando, Florida. On average, that's just over 6.8 hours of sleep a night.4 Beyond this, the data reveals how natural disasters impact your sleep.
During the South Napa earthquake that hit Northern California in 2014, 93 percent of wristband wearers near the epicenter suddenly woke up at 3:20 am, when the quake hit.5
Not surprisingly, most of them had a hard time going back to sleep afterward, and 45 percent of those near the epicenter did not go back to sleep for the rest of the night.
Also interesting, the data can reveal routines and characteristics about different cities. Brian Wilt, principal data scientist at Jawbone, summed up data of sleep patterns among seven US cities, collected on March 31, 2014, which he described as a "typical night."
"New Yorkers work hard and play hard, and they're the first to bed and among the first to rise. Users in Tokyo are among some of the last to go to bed and the first to wake up, since they only average five hours and 46 min of night sleep.
Dubai has the most leisurely sleep schedule, with 10% of users still asleep by 11am. In Beijing, you can see workers taking their afternoon workplace naps.
We can also see people in Madrid taking their afternoon sleep (although it's much more common on weekends, with greater than 10% of UP wearers logging a siesta). Only a maximum of 95% of a city is asleep at any given time, since the early risers are awake before the last to sleep are in bed."6
Do You Really Need Eight Hours of Sleep?
I used to think I was immune to needing adequate sleep. I would routinely get less than six hours a night and thought I could function this way. But I've since realized that most adults really need about eight hours of sleep every night.
When I first started using a fitness tracker, I was striving to get eight hours of sleep, but my Jawbone UP typically recorded me at 7.5 to 7.75.
I have since increased my sleep time, not just time in bed, but total sleep time to over eight hours per day, and the fitness tracker helped me realize that unless I am asleep, not just in bed, but asleep by 10 pm I won't get my eight hours. Gradually I have been able to get this down to 9:30 pm.
What makes sleep deprivation so detrimental is that it doesn't just impact one aspect of your health… it impacts many. For starters, your reaction time slows. One study even found that sleepiness behind the wheel was nearly as dangerous as drinking and driving.7
Your ability to think clearly is also dampened by lack of sleep, and as your reaction time and cognition slows, your emotions will be kicked into high gear. This means that arguments with co-workers or your spouse are likely and you're probably going to be at fault for blowing things out of proportion.
As for whether you, personally, need eight hours… the answer is probably yes. Your body is designed to compensate for less sleep than this here and there, but in the long run you're going to need adequate sleep or your health will suffer.
If you'd rather not measure your sleep down to the minute, Dr. Rubin Naiman -- a clinical psychologist, author, teacher, and the leader in integrative medicine approaches to sleep and dreams – recommends you simply sleep "enough hours.
Sleep so that your energy is sustained through the day without artificial stimulation, with the exception of a daytime nap," which he believes you are biologically programmed for.
I would add to this guideline the suggestion to watch out for physical or biological symptoms. For instance, frequent yawning during the day is a major red flag that you're sleep deprived, as is nodding off when you're reading or in a meeting.
If you need an alarm clock to wake up, and you wake up feeling tired and groggy, you probably need to go to sleep earlier (or get more restful sleep) as well.
It's also said that if you fall asleep within a few minutes of your head hitting the pillow, you're probably sleep deprived. A well-rested person will take about 10-15 minutes to fall asleep at night.8
Ongoing Lack of Sleep Comes at a Price
And that price is your health. Poor sleep can actually impact virtually every aspect of your health, and the reason for this is because your circadian rhythm (sleep-wake cycle) actually "drives" the rhythms of biological activity at the cellular level.
Even if you think can "get by" on five or six hours a night, you're not fooling your body. Sleep deprivation has the same effect on your immune system as physical stress or illness,9 which may help explain why lack of sleep is tied to an increased risk of numerous chronic diseases.
Sleeping less than six hours per night more than triples your risk of high blood pressure, and women who get less than four hours of shut-eye per night double their chances of dying from heart disease.10 Sleep is also intricately tied to important hormone levels, including melatonin, production of which is disturbed by lack of sleep. This is extremely problematic, as melatonin inhibits the proliferation of a wide range of cancer cell types, as well as triggers cancer cell apoptosis (self-destruction).
Lack of sleep also decreases levels of your fat-regulating hormone leptin while increasing the hunger hormone ghrelin. The resulting increase in hunger and appetite can easily lead to overeating and weight gain. And according to research from Great Britain, poor or insufficient sleep is actually the strongest predictor for pain in adults over 50,11 and people with chronic sleep problems may develop Alzheimer's disease sooner than those who sleep well.12 Besides making you more susceptible to physical aches and pains, interrupted or impaired sleep can also:
- Increase your risk of cancer
- Harm your brain by halting new neuron production. Sleep deprivation can increase levels of corticosterone (a stress hormone), resulting in fewer new brain cells being created in your hippocampus
- Contribute to a pre-diabetic state, making you feel hungry even if you've already eaten, which can lead to weight gain
- Contribute to premature aging by interfering with your growth hormone production, normally released by your pituitary gland during deep sleep (and during certain types of exercise, such as high-intensity interval training)
- Increase your risk of dying from any cause
This Is Your Brain On Too Little Sleep…
The next time you're resisting the urge to nod off in favor of a Netflix marathon, consider this: sleep is necessary for maintaining metabolic homeostasis in your brain. Wakefulness is associated with mitochondrial stress, and without sufficient sleep, neuron degeneration sets in.
In one animal study, inconsistent, intermittent sleep (similar to what might be experienced by shift workers) resulted in remarkably considerable and irreversible, brain damage — the mice actually lost 25 percent of the neurons located in their locus coeruleus, a nucleus in the brainstem associated with arousal, wakefulness, and certain cognitive processes.13
As reported by Time magazine:14
"The scientists believe that when the mice slept inconsistently, their newer cells would create more sirtuin type 3, a protein meant to energize and protect the mice. But after several days of missing sleep, as a shift worker might, the protein creation fell off and cells began to die off at a faster pace."
Further, according to research published in the journal Neurology, lack of sleep may affect the size of your brain.15 A total of 147 adult volunteers underwent MRI scans to assess the link between sleep and brain volume. As it turns out, sleep problems like insomnia can have a distinct impact on your brain over time, causing it to shrink — and shrink more rapidly — compared to those who sleep well. This effect was particularly significant in those over 60, which shows just how important quality sleep is at all life stages.
Ready for the Best Night's Sleep You've Had in a While?
Small adjustments to your daily routine and sleeping area can go a long way to ensure uninterrupted, restful sleep and, thereby, better health. If you're not sure how much sleep you're getting, a fitness tracker can be beneficial for helping you keep track of the actual time you're asleep (as opposed to the time spent in bed). If you need more sleep, I suggest you read through my full set of 33 healthy sleep guidelines for details on proper sleep hygiene, but to start, consider implementing the following changes:
- Avoid watching TV or using your computer in the evening, at least an hour or so before going to bed. These devices emit blue light, which tricks your brain into thinking it's still daytime. Normally, your brain starts secreting melatonin between 9 pm and 10 pm, and these devices emit light that may stifle that process. Even the American Medical Association now states:16
"…nighttime electric light can disrupt circadian rhythms in humans and documents the rapidly advancing understanding from basic science of how disruption of circadian rhythmicity affects aspects of physiology with direct links to human health, such as cell cycle regulation, DNA damage response, and metabolism."
- Make sure you get BRIGHT sun exposure regularly. Your pineal gland produces melatonin roughly in approximation to the contrast of bright sun exposure in the day and complete darkness at night. If you are in darkness all day long, it can't appreciate the difference and will not optimize your melatonin production.
- Sleep in complete darkness, or as close to it as possible. The slightest bit of light in your bedroom can disrupt your body's clock and your pineal gland's melatonin production. Even the tiniest glow from your clock radio could be interfering with your sleep, so cover your radio up at night or get rid of it altogether. Move all electrical devices at least three feet away from your bed. You may want to cover your windows with drapes or blackout shades. If this isn't possible, wear an eye mask.
- Install a low-wattage yellow, orange, or red light bulb if you need a source of light for navigation at night. Light in these bandwidths does not shut down melatonin production in the way that white and blue bandwidth light does. Salt lamps are handy for this purpose. You can also download a free application called F.lux that automatically dims your monitor or screens.17
- Keep the temperature in your bedroom no higher than 70 degrees F. Many people keep their homes too warm (particularly their upstairs bedrooms). Studies show that the optimal room temperature for sleep is between 60 to 68 degrees F.
- Take a hot bath 90 to 120 minutes before bedtime. This increases your core body temperature, and when you get out of the bath it abruptly drops, signaling your body that you are ready to sleep.
- Avoid using loud alarm clocks. Being jolted awake each morning can be very stressful. If you are regularly getting enough sleep, you might not even need an alarm.
- Get some sun in the morning, if possible. Your circadian system needs bright light to reset itself. Ten to 15 minutes of morning sunlight will send a strong message to your internal clock that day has arrived, making it less likely to be confused by weaker light signals during the night. More sunlight exposure is required as you age.
- Be mindful of electromagnetic fields (EMFs) in your bedroom. EMFs can disrupt your pineal gland and its melatonin production, and may have other negative biological effects as well. A gauss meter is required if you want to measure EMF levels in various areas of your home. Ideally, you should turn off any wireless router while you are sleeping. You don't need the Internet on when you are asleep.