One in five Canadians uses wearable devices such as smart watches or rings to monitor their sleep, according to a national survey.FRANK GUNN/The Canadian Press
The Sleep Whisperer is a series of columns offering insights and advice about sleep health. It is not a substitute for seeking professional medical care.
Technology has found its way into nearly every corner of our daily lives – including, increasingly, our bedrooms, with the use of sleep-tracking wearables. This is part of a broader cultural shift toward the “quantified self,” a desire to track everything from steps taken to hours slept – all in the name of self-optimization.
In a national survey, a group of sleep researchers including me recently found that one in five Canadians uses wearable devices such as smart watches or rings to monitor their sleep.
Unsurprisingly, we found that individuals living with sleep disorders are among the most likely to adopt these devices. For many, this may reflect a desire to take charge of their own sleep health.
A Beddr SleepTuner, a sleep tracker worn on the forehead. For some, feedback from such devices can lead to orthosomnia, an unhealthy pursuit of the “perfect” sleep that leads to anxiety and, paradoxically, sleeplessness.DAN KOECK/The New York Times News Service
Do sleep trackers actually help?
The short answer: It’s complicated.
Of the users we surveyed, 45 per cent said their tracker had a positive impact on their sleep, while 4.5 per cent felt this made their sleep worse.
While the proportion of respondents who said wearables had a negative impact on their sleep was relatively small, it nonetheless highlights a new kind of sleep problem that experts have been sounding the alarm about: orthosomnia.
This term orthosomnia refers to an unhealthy and perfectionistic pursuit of the “perfect” sleep – often triggered by the feedback from wearable devices. The result? Paradoxically, anxiety about sleep performance that makes it harder to sleep in the first place.
How accurate are sleep trackers?
Sleep trackers can sometimes provide a decent estimate of how many hours you are sleeping, but they may not get all the details right – including sleep stages.
The accuracy of sleep trackers varies widely based on several factors, including the types of sensors and the specific sleep metric you are looking at. Some models detect only movement – relying on the assumption that stillness means sleep. For good sleepers, this can offer a rough estimate of sleep duration, but for those who lie awake quietly, struggling to fall asleep, these devices can overestimate sleep. Likewise, long sedentary periods – for example, reading in bed – can be falsely counted as sleep.
Things get even murkier when it comes to sleep stages or depth, which are determined by variations in brain waves. Relying solely on motion or breathing sounds to make inferences about brain activity – like many smartphone apps or basic wristbands are attempting to do – is rather far-fetched. The claims these types of devices make about REM, light or deep sleep are speculative at best.
If your device includes a heart rate sensor, it may have a better level of precision since this biosignal undergoes systematic variation across sleep stages. Yet, even this remains an indirect estimation.
The Oura Ring 4. While sleep trackers vary in accuracy, many rely on motion or breathing sounds to determine sleep stages, meaning their data on REM, light or deep sleep is speculative at best.ANDRIA LO/The New York Times News Service
It is also worth noting that many commercial sleep trackers were designed based on data from relatively homogeneous populations – typically healthy, young, white males with regular sleep schedules. This leaves important gaps in how these tools perform for people outside that demographic, such as older adults, shift workers, individuals with medical conditions, people going through hormonal variations and even people with darker skin tones (which can affect optical sensors).
As a result, although sleep trackers may work well for some people, consumers are often left with little insight into the reliability of these devices for their unique situations.
If your tracker’s readout doesn’t match how you feel you slept, chances are you’re not imagining it.
In my view, some of the most exciting advances in this field are the emergence of portable monitors capable of recording actual brain activity. These open a more direct window into sleep stages and the finer features of sleep architecture. Looking ahead, I think accurate sleep trackers may eventually help identify subtypes of insomnia, flag insidious yet treatable conditions such as sleep apnea and tailor treatments to personal sleep profiles.
So, when are sleep trackers actually helpful?
More work is required to better understand this, but for now I think the key lies in how they are used.
Early research suggests that sleep quality may improve if we leverage trackers to identify optimal bed and wake times and map other lifestyle factors that influence our sleep – such as daytime exercise. Yet, checking sleep stats at bedtime or during the night can trigger stress, particularly in those of us who are prone to sleep anxiety or insomnia. It may be best to digest that information during the daytime.
Also, keep in mind that if you are getting overly preoccupied about your sleep data, you may be heading toward orthosomnia. You may need a tracking break for a few weeks. After reconnecting with your natural sleep, ask yourself how rested you really feel during the day. If still in doubt about your sleep, talk to a sleep specialist.
Dr. Rébecca Robillard, PhD, is a clinical neuropsychologist and associate professor at the School of Psychology at the University of Ottawa. She also leads clinical sleep research at the Royal. Robillard’s main area of work focuses on interactions between mental health, the sleeping brain and the sleeping heart. She co-chairs the Canadian Sleep Research Consortium, a national hub of sleep scientists and clinicians.
