Sleep tracking sounds like a dream. You get a gadget that tells you how you slept and then gives you tips to sleep better and – boom – you’re better rested. As a parent of a young child, I know this isn’t the way it would work for me, but I’ve been feeling desperate lately. If I sleep less, maybe I can just sleep smarter with the help of a wearable.
That’s how I got involved with the promise of the Oura Ring, a $350 device you wear on your finger that can measure a number of different health metrics, including sleep. You’ve probably seen a celebrity wearing one in the tabloids. Mark Zuckerberg wears one to optimize his sleep.
The big problem is that wearables offer no guarantees whatsoever. This fall, we’ve seen these gadgets gain new capabilities, like detecting sleep apnea and working as hearing aids, making wearables increasingly resemble medical wonders. However, research over the years has shown that doctors currently don’t find the data from these devices very useful in a clinical setting, and if left to their own devices could make consumers feel worse about using a wearable. The positive effects of sleep trackers are particularly difficult to determine.
But if I just wanted a few data points that would lead me to better habits, a little ring certainly wouldn’t hurt. After a few days of scouring medical journals to make a better decision about what a wearable could do for my sleep, I now feel more exhausted than ever. Buying a new gadget doesn’t solve this for a number of reasons. Nevertheless, if you’re considering using a wearable to improve your health, it’s helpful to know where the marketing ends and the proven benefits begin.
Despite what the marketing suggests, very few wearables have been approved by the FDA
The Oura Ring 4, which will be released this week, uses various lights and sensors to measure your heart rate, breathing rate, blood oxygen, temperature and movement. For an additional $6 monthly membership fee, you get access to things like detailed sleep analysis, advanced temperature monitoring, and reproductive health insights. The ring has no screen; it connects to your phone via Bluetooth, so you can see all your health data there.
The Oura ring “is not a medical device.” This is the first thing the company’s PR team told me when I contacted them for this article. However, Oura often mentions the potential health benefits in its marketing, and it prominently promotes its medical advisory board on its website. Jason Russell, Oura’s vice president of consumer software, explained that the company is responding to real demand.
“People want to understand their body and live long, healthy lives, but they don’t want another technical device to manage it,” Russell said, emphasizing the discretion of the Oura ring.
You can also use the money from your health savings account (HSA) and flexible spending account (FSA) to buy an Oura ring, which is confusing because you’re only allowed to use it for medical and dental expenses. The Oura ring does not have FDA approval, although it can be used with the FDA-approved Natural Cycles menstrual cycle tracking app. According to some reviewers, it is especially useful for women for this very reason. Natural Cycles describes itself as “a hormone-free alternative to the pill that is 93% effective with normal use.”
This maze of regulations and approvals makes it difficult to know whether the Oura ring, which is marketed as a device that can improve your health, offers real medical benefits. The same goes for other wearables, such as the Apple Watch, which recently received FDA approval for detecting sleep apnea. That’s in addition to the fact that the device is FDA-approved for detecting irregular heart rhythms and recording electrocardiograms. (Smartwatches and fitness trackers from Google, Samsung and Fitbit have similar approvals.) Even Apple AirPods Pro received FDA approval this year for a new feature that turns them into “the first over-the-counter (OTC) hearing aid software.” device.”
None of these devices have been approved by the FDA. There is a difference between FDA approval, which is a very complicated process, and the less rigorous FDA approval. There is also a third designation called ‘de novo classification’, reserved for low-risk devices that do not yet exist on the market. (The new hearing aid feature on the AirPods Pro recently received this designation.) The FDA recognizes that its name is being thrown around in misleading ways, so much so that it has an entire explanation of what FDA approval actually means.
So while I can use this year’s leftover FSA dollars to buy an Oura ring, the FDA hasn’t put a stamp of approval on the device. Thanks to the partnership with Natural Cycles, the Oura Ring does enjoy a bit of that FDA-approved shine, but that has nothing to do with the rest of its features.
Either way, you’d be forgiven for thinking that a device you can buy with money set aside for health care costs from a company the FDA name-checks in its press release would lead to health benefits. When it comes to wearables, this is not always the case.
What wearables do for our health
Ultimately, you may not need a stamp of approval from a government agency to know if a gadget is useful to you. I bought an Apple Watch not because I wanted something that would alert me to an irregular heartbeat, but because I liked getting notifications on my wrist. It’s easier to check a text message on my watch than to pull out my phone. The fitness tracking that comes with the watch is a bonus, and I can confidently say that I’m moving my body more because my watch tells me to.
Research shows that smartwatches and other fitness trackers are best at this. A systematic review of almost 200,000 study participants, published in the Lancet 2022 found that wearables did indeed improve physical activity and help people lose weight. People who wore fitness trackers walked an average of 1,800 extra steps per day. But they had little effect on other health markers, including blood pressure and cholesterol. A smaller meta-analysis in the BMJa peer-reviewed journal from the British Medical Association, came to similar conclusions: more than 1,200 extra steps per day. It seems that fitness tracking leads to better fitness.
Tracking sleep is not so clear. Whether you wear it on your wrist, under your mattress, or wrapped around your finger, a sleep tracker measures everything from your movement and body temperature to your heart rate and blood oxygen to determine how long you slept and how well. The idea here is that by having more details about how you slept, you can link what you did before bed – for example, vigorous exercise, drinking, or doomscrolling on your phone – to your sleep quality. If bad habits lead to bad sleep, you can stop the bad habits.
Many sleep trackers process all that data through an algorithm that spits out a score. (The Oura Ring app gives you three scores: one for sleep, one for activity during the day, and one for “readiness,” which tells you on a scale of 1 to 100 how ready you are for the day.) Experts warn that these scores may be arbitrary, if not downright useless. Furthermore, most trackers cannot directly measure brain activity, which is the standard for diagnosing sleep disorders. Plus, obsessing over sleep data, scores and metrics can actually increase anxiety and lead to poorer sleep, according to a recent study from the American Academy of Sleep Medicine.
It is possible that some of this data could be useful in a clinical setting. According to a study, newer Apple watches can produce an ECG that’s about as good as what you’d get from a doctor. The problem is that for the time being it is not always easy for doctors to access the data collected by wearables. This isn’t to say that doctors aren’t optimistic about a future where they can access that data. Many doctors are telling their patients to buy wearables and use them to help manage diseases, especially heart-related problems that devices like the Apple Watch are designed to detect.
Medical device or not, all wearables have pros and cons, largely depending on how you use them. The Oura Ring rabbit hole I fell into made me feel more confident about how I used the wearable device I own, my Apple Watch. It also put me off buying an Oura ring.
To be clear, I haven’t tried the new Oura ring yet, so I’ll hold off for now. Even though I still have some FSA funds to spend before the end of the year, I think the sleep tracking feature would make me anxious in the long run.
At this stage in my life, sleeping smarter isn’t exactly an option. I simply need more hours in the day, and that gadget hasn’t been invented yet.
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