Do Fitness Tracking Watches & Rings Actually Make Us Healthier?
Your fitness tracker is giving you data. But is it giving you the right kind?
Prefer to listen to a human conversation?
A patient sent a message through the portal. Attached was a PDF — several pages, color-coded, meticulously laid out — of data from his Oura ring. His deep sleep had been down for two weeks. He was tired. He snored, which his wife had been mentioning for years. He hadn’t thought much of any of it, separately. But the ring made it feel like a pattern. Like something worth bringing up.
He got a home sleep test. His apnea-hypopnea index came back at 16. He started CPAP. His sleep scores improved.
That’s one version of this story.
Here’s another. A patient called about ten days into a respiratory illness. She was still congested, still coughing, still blowing her nose. She was worried she’d developed a sinus infection. The reason she called? Her Oura ring, which had been quiet for several days, was now flagging “mild signs of stress” again — after starting the illness with “major signs of stress,” then settling down, then spiking again. The ring felt like confirmation that something was off.
Classic post-viral sinusitis symptoms, it turned out. She recovered without antibiotics.
Two patients. Same device. One case where the data nudged someone toward a real diagnosis they’d been avoiding. One case where the data may have prompted an unnecessary call about symptoms that didn’t require intervention.
This is the honest complexity behind a question a lot of people are asking right now: can a watch or a ring actually help us optimize our health?
The Claim
The pitch for consumer wearables — Oura Ring, Apple Watch, Fitbit, Garmin, and their many competitors — goes something like this: if you have enough data about your own body, you can use that data to make smarter decisions about your health. You can optimize your sleep, your activity, your recovery. You can catch something early, before it becomes a problem. The data doesn’t lie. And if you aren’t tracking, you might be missing something.
The marketing also carries a cultural implication: that traditional healthcare is reactive — waiting until you’re sick to do anything — while wearables represent a more personalized, proactive, precision approach. Continuous monitoring. Real-time feedback. A gold star at the end of the day if you closed your rings.
Why It’s Going Viral
The appeal makes sense on multiple levels.
There’s the very real cultural obsession with optimization right now. Wellness content is among the highest-performing content on every major platform. The idea that you could be doing more, tracking more, understanding your body more deeply — that’s in the water right now.
There’s also FOMO. Someone gets a device and starts sharing what it’s telling them about themselves, and suddenly you wonder: what might mine tell me? What am I missing?
And underneath both of those is something more serious — the fear of an unexpected health event. We all see the GoFundMe. The person who was seemingly fine. The diagnosis that came out of nowhere. If data could have caught it earlier, shouldn’t we have the data?
There’s also something worth naming that goes a little deeper: many of us have become genuinely disconnected from our own physical experience. So much of life is digital, virtual, mediated through screens. We’re flooded with notifications and input. We’ve been trained — by hustle culture, by demanding employers, by a healthcare system that requires documentation before you’re allowed to be sick — to push through, dismiss our symptoms, and not trust what our bodies are telling us. In that context, a wearable that delivers objective data about your own body can feel like permission. It can feel like proof. My ring says I’m stressed, so I’m allowed to acknowledge that I’m stressed.
That’s not silly. That’s a symptom of something bigger. And it helps explain why these devices have taken hold the way they have.
What the Science Shows
Step counting and activity tracking
This is the most basic use case, and the one with the most straightforward evidence.
Is it accurate? A comparison study of consumer wearables against a research-grade actigraph found that Apple Watch and Oura Ring were both within 10% of the gold standard for step counting, while Fitbit overestimated by about 18%. Moderate-to-vigorous activity measurement was more variable. Calorie burn estimates — the number that tells you how many calories you burned — showed the largest discrepancies, with Fitbit overestimating by over 139%. So: step count, reasonably accurate.
Does it matter? According to a large JACC review of consumer wearables in cardiovascular medicine, yes — there’s actually evidence that step counting helps people with cardiometabolic conditions (diabetes, cardiovascular disease, obesity) increase their physical activity and improve key health metrics over time. The accountability function is real.
Atrial fibrillation detection
Is it accurate? The Apple Heart Study enrolled over 400,000 participants to evaluate the Apple Watch’s irregular pulse notification algorithm. When participants received a notification, about 34% were confirmed to have atrial fibrillation on follow-up ECG patch. The positive predictive value was 0.84 — meaning when it flagged something, it was right about 84% of the time. That’s a reasonably strong signal.
Does it matter? Importantly, it doesn’t tell us how often the watch misses cases, because no follow-up was done on the unnotified participants. Another notable finding: 57% of notified participants contacted a healthcare provider outside of the study. That’s a lot of people entering the healthcare system because of a wrist notification — some of whom needed to, and some of whom may not have.
Heart rate variability
Is it accurate? This is one of the most commonly asked-about metrics — and one of the most confusing. HRV is a measure of how much variation exists between heartbeats, used as a proxy for autonomic nervous system health and recovery from stress. Higher HRV generally indicates better cardiovascular fitness, lower stress, and better sleep. Lower HRV is associated with illness, poor recovery, chronic stress, aging, and being female (for reasons that aren’t fully understood).
Does it matter? Consumer wearables have mean absolute percentage errors of 29–31% compared to ECG-based measurement, and they’re least accurate when you’re moving. More fundamentally, there are no validated clinical norms for HRV. There’s no number you “should” have. What has potential value is your own trend over time — a sustained drop for you, relative to your baseline, may indicate something worth paying attention to. But the absolute number is not clinically interpretable, and there’s no “good” or “bad” HRV score to compare yourself against.
Sleep tracking
Is it accurate? A study comparing the Oura Ring Gen 3, Fitbit Sense 2, and Apple Watch Series 8 against polysomnography — the gold-standard sleep study — found that all three devices were reasonably accurate at distinguishing sleep from wakefulness (sensitivity over 95%), and similar to the gold standard in estimating total sleep duration. The Oura Ring performed best at estimating sleep stages. The Fitbit and Apple Watch showed more variability — the Apple Watch underestimated deep sleep by 43 minutes.
Does it matter? One clinically relevant development: a Samsung smartwatch feature received FDA authorization in 2023 to detect signs of moderate-to-severe sleep apnea. Sensitivity was 82.7% and specificity 91% — not bad for a screening tool. It’s not a diagnosis, can’t replace a polysomnography, and only flags moderate to severe cases. But it’s the first consumer wearable feature with FDA authorization for this purpose.
Who’s actually using these devices — and who benefits most
This is a critical piece of context from the same JACC review: only about 30% of US adults use wearable devices, and adoption is concentrated among younger, wealthier, more educated, and already-healthier individuals who are already exercising regularly. In other words, the people most likely to benefit — those with cardiometabolic risk, those who are sedentary — are the least likely to be wearing these devices. And importantly, the evidence suggests that wearable interventions are significantly more effective when paired with face-to-face clinical conversations rather than used in isolation.
Clinical Nuance
None of this means wearables are useless, or that the patients using them are being naive. It means the picture is genuinely complicated.
There are clinical situations where these devices have real value. A patient who’s been snoring for years and keeps dismissing their spouse’s concerns might finally get a sleep study because their ring flagged something. A patient at risk for atrial fibrillation might catch an asymptomatic episode earlier than they would have otherwise. A patient with diabetes who’s been sedentary might find that step-count tracking gives them the accountability nudge they needed. These aren’t trivial benefits.
But there are also real risks. The psychological burden of constant data can be significant — and it’s underrecognized. For patients with anxiety, OCD, eating disorders, or perfectionistic tendencies, wearables can become a source of distress rather than reassurance. The compulsion to close every ring, even when sick. The spiral that begins when a metric drops. The notification that arrives at 11pm telling you your HRV is low. These are not benign side effects.
There’s also the cascade effect. False positive notifications don’t just cause anxiety — they trigger healthcare contact. And primary care providers are already working in a system that estimates it would take 26.7 hours per day for a single physician to provide all recommended adult preventive care for a panel of 2,500 patients. Every portal message with a screenshot of wearable data is one more thing that needs a response — sometimes warranted, sometimes not.
Finally, there’s the question of false reassurance. A person who can’t access or afford traditional healthcare, who uses a wearable as a substitute for evidence-based screening, may feel like they’re covered when they’re not. These devices don’t check your blood pressure in a clinically meaningful way. They don’t screen for diabetes or thyroid disease. A “clean” Oura ring readout does not replace a screening mammogram or colonoscopy.
The most useful framework may be: these devices can be a bridge — to motivation, to a conversation, to taking something seriously that was previously being dismissed. They are not a destination.
The Antidote
For Patients
(Things you can remind yourself when your wearable is making you anxious, confused, or compulsive)
I am allowed to trust how I feel without needing a device to confirm it.
A low HRV score or a rough sleep readout is not a diagnosis. It’s one data point.
The goal of tracking is to support my wellbeing — not to add another thing to optimize or feel bad about.
If this device is adding to my anxiety rather than reducing it, I’m allowed to take it off.
The best version of caring for my health includes actual conversations with my doctor — not a substitute for them.
I can bring my wearable data to my appointment and talk through what it does and doesn’t mean.
More information is not always the same as better information.
For Clinicians
(Language you can borrow, tweak, or make your own)
“What about this device has been most helpful for you? Has it shown you anything that caused you stress or confusion?”
“Heart rate variability doesn’t have a clinical normal range — what matters more is your own trend over time, not comparing it to a number online.”
“This is one piece of information. It doesn’t replace the conversation we’re having about how you’re actually feeling.”
“For some of my patients, trackers are a really useful nudge toward activity or sleep habits. For others, they become a source of anxiety. I want to make sure it’s doing the first thing for you, not the second.”
“If your watch flags an irregular rhythm, that’s worth bringing to me — but it doesn’t mean something dangerous is happening. Let’s talk about what follow-up actually makes sense.”
“Wearable data can be a great conversation starter. It can’t replace the actual evaluation.”