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Apple Watch 6 blood oxygen reader — here's why SpO2 monitoring is a big deal

Apple Watch 6
(Image credit: Tom's Guide)

Apple Watch SpO2 monitoring is coming to Apple Watch 6, joining its catalog of health-tracking features that can, in certain instances, save lives. It will feature also fall detection, which can call emergency services on your behalf, as well as an ECG monitor that can reveal signs of atrial fibrillation. 

Now that Apple is making SpO2 monitoring more relevant in the wearable space, it could benefit you to know how the technology works, what it can inform and whether it's a viable detector of respiratory viruses.

Apple Watch 6 blood oxygen monitoring: What is SpO2?

Blood oxygen sensors can measure the oxygen saturation level of your blood. As a form of pulse oximetry, SpO2 monitoring in the Apple Watch 6 would let users know when their blood oxygen falls below a certain concentration. Below-normal levels of blood oxygen concentrations are often indicative of underlying health issues such as sleep apnea.

If you wake up feeling unrested in the morning, SpO2 readings might tell you if low blood oxygen levels are causing you to stir throughout the night. Tedious sleep studies in the care of a doctor are often required to receive an official sleep apnea diagnosis, but a smartwatch or fitness tracker could save you some time.

The Apple Watch isn't be the first wearable with SpO2 — its fitness-tracking rivals Garmin and Fitbit have already introduced blood oxygenation sensors to several models in their lineups. As noted in our Fitbit Charge 4 review, the SpO2 monitor is specifically used for recognizing breathing difficulties while you sleep.

Newer options like the Samsung Galaxy Watch 3, Withings ScanWatch and soon-to-be-released Fitbit models boast this function, too.

Apple Watch SpO2 monitoring could be a game-changer for sleep tracking

So why is it a big deal that the Apple Watch has blood oxygen monitoring when several wearables already have it? 

For one, with Apple Watch sleep tracking out, SpO2 readings could accentuate the otherwise-simple sleep tracking data currently supported by the company’s native sleep app. 

But the bigger picture here is Apple cementing the fact that it doesn’t need to be first to the party on every smartwatch feature. Its legions of users are loyal enough to wait for tools, or at least complacent enough to be told when tools matter. 

In other words, it’s possible Apple is about to make SpO2 monitoring much more relevant in the wearable category.

Apple Watch SpO2 monitoring: Will it detect COVID-19?

It’s also possible that, in the timely battle against COVID-19, the appeal of SpO2 monitoring will be tied to the Apple Watch 6. Pulse oximetry is able to detect silent hypoxia, a life-threatening condition that can escalate the effects of the coronavirus.

In an op-ed for The New York Times published in April, emergency doctor Richard Leviathan says widespread pulse oximetry "could provide an early warning system for the kinds of breathing problems associated with Covid pneumonia."

According to Dr. Leviathan, pulse oximeters are "extremely reliable" in identifying coronavirus warning signs like heightened heart rates and subtle oxygenation issues.

That said, the Apple Watch 6 getting SpO2 monitoring doesn't mean it can offer a coronavirus diagnosis, or let people know earlier on that they could be sick and should quarantine. 

I repeat, the Apple Watch 6 will not be able to detect coronavirus.

It could, however, be pitched as an insightful tool in the continuing pandemic. At the very least, irregular SpO2 readings could lead people to a medical professional sooner than obvious symptoms would.