Do Sleep Trackers Work? 8 Things Sleep Doctors Want You to Know

But experts warn that what you can learn from your sleep stats, at least currently, has its limits.

1. Sleep Trackers Are Not Medical Devices

2. The Data May Not Be Accurate

Those numbers on your tracker may not be entirely correct.

"Many sleep trackers use an accelerometer, a device that measures how much you move, to estimate sleep," says Michelle Drerup, PsyD, the director of behavioral sleep medicine at the Cleveland Clinic's Sleep Disorders Center in Ohio. If you spend time in bed reading or scrolling through your phone, the lack of movement will likely register as light sleep, she notes.

By the same token, if you wake up in the middle of the night and stare at the ceiling without moving, the tracker won't register you're awake. It’s important to know that the data can be flawed in these ways, says Kelly Glazer Baron, MPH, PhD, a clinical psychologist with specialty training in behavioral sleep medicine and a professor at the University of Utah in Salt Lake City.

3. The Most Accurate Sleep Tests Monitor Brain Waves

4. Trackers May Encourage Technology Use Before Bed

If your phone or another device is near you in bed so it can track your sleep, you may be more likely to hear alerts for incoming texts and emails when trying to fall asleep, Drerup says. The ideal bedroom setting is device-free. "Devoting the bed and bedroom to being a calm, relaxed environment is essential for having a healthy relationship with sleep," Drerup says.

5. Sleep Trackers May Help You Notice Certain Sleep Patterns

The main health benefit of trackers is they can help you recognize patterns in behavior that may affect your health. "A sleep tracker can be helpful if you are trying to extend or lengthen sleep time because you don't allow enough time for sleep because of a busy schedule or a tendency to binge-watch television shows before bedtime," Drerup says. They can be a reality check for how many hours of shut-eye you are actually logging every night — and how many days in a week or month you are cutting your rest short, she says.

6. Over-the-Counter Sleep Trackers Can’t Diagnose  Sleep Disorders

The landscape around sleep trackers is changing, and the technology is quickly improving. Currently, many of the commercially available sleep trackers are not designed (or FDA-approved) to diagnose sleep disorders or other health problems.

7. For Some People, Use of Sleep Trackers May Worsen Sleep Struggles

Interestingly, sleep trackers can make insomnia worse if people (in an attempt to sleep longer) end up spending more time in bed lying awake. "It may seem counterintuitive, but part of the behavioral treatment for chronic insomnia is to actually spend less time in bed trying to sleep," Dr. Baron says.

Indeed, experts say that spending too much time in bed not sleeping can actually train the brain to associate your bed with not sleeping or unsuccessfully trying to fall asleep. And they also caution that over-attention to your sleep numbers in general can cause a level of anxiety that (you guessed it) interferes with your sleep.

8. Tracker Data May Be a Game Changer for Sleep Researchers

The fact that your sleep last night was 20 minutes shorter than your nightly average generally doesn't have sweeping implications for your health.

The Takeaway

• Sleep trackers, though popular, are not FDA-approved to diagnose or treat sleep disorders and should not replace professional medical evaluations.
• These devices can offer helpful insights into general sleep patterns and may even signal symptoms of a sleep disorder that warrant a doctor's visit, but inaccuracies can occur.
• Sleep studies in labs remain the gold standard for diagnosing sleep disorders, as they closely monitor multiple indicators of sleep, including brain wave activity, eye movement, and breathing patterns.
• If you suspect a sleep disorder or experience persistent fatigue, seeking the advice of a healthcare provider is crucial rather than relying solely on tracker data.