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The newcomes with a and app to give you more ways to monitor your heart and respiratory health. Together they measure your oxygen saturation (SpO2) in your blood — how much oxygen from your lungs your red blood cells pick up and transport to all of the other parts of your body.
Low blood oxygen levels, or hypoxemia, have been linked to because the disease affects your ability to get enough oxygen. Doctors have used SpO2 levels to determine the severity of COVID-19 cases and treat those patients accordingly.
But hypoxemia can be caused by many other heart and lung issues, such as asthma, pneumonia and congenital heart disease. By monitoring your SpO2, your Apple Watch might be able to warn you of potential health issues before you realize you have them, or at least that’s Apple’s hope anyway.
Here’s how to use the Blood Oxygen feature on the Apple Watch Series 6 — it’s currently only available for the Series 6, not any other models.
How does the blood oxygen sensor work?
The blood oxygen sensor is built into the back of the Apple Watch. It uses four clusters of red, green and infrared LED lights and four photodiodes, devices that convert light into an electrical current. The lights shine onto the blood vessels in your wrist and the photodiodes measure how much light bounces back.
I won’t get into the medical specifics, but essentially oxygenated and deoxygenated blood absorb red and infrared light differently, so the light that bounces back allows the Apple Watch to determine the color of your blood.
Bright red blood is oxygenated, while dark red blood has less oxygen, either because it’s been delivering oxygen to your organs and muscles or it’s not getting enough oxygen from your lungs.
If you want to dig into exactly how pulse oximeters work, check out this article published in the Respiratory Medicine medical journal.
How do you use the Blood Oxygen app?
With the Apple Watch Series 6, you can get an on-demand reading of your SpO2. Just open the app and follow the prompts on the screen.
The reading takes 15 seconds, and once it’s done you’ll see the percentage of oxygen in your blood pop up on the watch screen.
The watch will also take periodic readings throughout the day when you’re inactive, like when you’re lying on the couch or sleeping. All of your blood oxygen readings will sync to the.
The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.