In our modern age of health optimization, sleep is no exception. We want the best rest in the least amount of time. We are increasingly turning to sleep- tracking devices to find it.
The focus on improving sleep is welcome, given its vital role in health. There are, however, pitfalls to relying on technology when the solutions to better sleep require behavioral change that can be achieved without technology.
Unlike sleep studies used by clinicians, which directly measure brain waves, sleep trackers such as watches and rings measure signs that are correlated with sleep — like heart rate, temperature, oxygen, breathing, snoring and movement. From those signs, the trackers estimate sleep measures like duration, stages and interruptions.
Most trackers, unfortunately, haven’t been compared with sleep studies in peer-reviewed research, so their accuracy is unknown. Results of scientific evaluations have been mixed. A 2021 article in the journal Sleep reported that seven trackers could detect when someone was asleep but inconsistent at identifying sleep stages.
Accuracy aside, the question remains whether trackers actually improve sleep. Basic information like the window and duration of time in bed, which the trackers measure, are important to know because they are modifiable behaviors that can impact sleep quality. Trackers conveniently measure these factors, but a clock, pen and paper can achieve the same aim.
It is unclear, however, whether detailed, tracker-collected data such as sleep stages helps improve sleep. The critical steps needed to improve sleep are behavior changes. If tracking sleep details motivates those changes, that could benefit users.
For some people, tracking detailed data about sleep may actually be harmful.
Sleep is a natural automatic process. Like breathing, it can be interfered with if the mind pays too much attention to it. Trackers may encourage some people to develop an unhealthy obsession with sleep, which could lead to insomnia. A 2017 case report in the Journal of Clinical Sleep Medicine coined the term “orthosomnia” to characterize this problem. The term refers to an unhealthy obsession with achieving perfect sleep data.
For some, the morning ritual of checking a sleep score creates a cycle of anxiety. If the tracker says they had poor sleep, they may feel tired and stressed all day — even if they actually felt fine before they checked their score.
As a sleep physician, I see some patients who trust their trackers more than their own perceptions. A patient might worry about “fragmented sleep” or a “lack of deep sleep” reported by their watch. Yet when I ask how they feel, they admit they don’t remember waking up and generally feel rested.
In sleep medicine, perception matters. A diagnosis of insomnia requires that an individual actually feels bothered by their sleep.
For the typical healthy person, knowing what to do to improve their sleep is simple. Here is the short list:
- Prioritize a consistent window of at least seven hours in bed.
- Create a sleep space that is dark, quiet and comfortable.
- Exercise daily and get outdoor light in the morning.
- Eat a healthy diet and allow adequate time to digest before bed.
- Avoid using electronics in bed.
When approached with curiosity, trackers may be useful in conveniently monitoring sleep and motivating positive change. But don’t underestimate the value of healthy sleep habits and paying attention to how you feel.
