Does Apple Watch automatically track Blood Oxygen?

Answered by Frank Schwing

The Apple Watch does have a blood oxygen sensor built into its back, but it does not automatically track blood oxygen levels. Instead, the sensor can be used on-demand by the user to measure their blood oxygen saturation levels.

The blood oxygen sensor on the Apple Watch works by using clusters of red, green, and infrared LED lights, as well as photodiodes. These LED lights shine onto the blood vessels in the user’s wrist, and the photodiodes measure how much light is reflected back. By analyzing the amount of light that is absorbed by the blood vessels, the Apple Watch can estimate the oxygen saturation levels in the user’s blood.

To use the blood oxygen sensor on the Apple Watch, users need to open the Blood Oxygen app on the device. They then need to rest their arm on a table or other flat surface, and keep their wrist steady and still. The Apple Watch will then start the measurement process, and after 15 seconds, it will display the blood oxygen saturation level on the screen.

It is important to note that the blood oxygen sensor on the Apple Watch is not intended for medical use. It is designed to provide users with a general understanding of their blood oxygen levels, but it is not a substitute for professional medical advice or diagnosis.

In my personal experience, I have found the blood oxygen sensor on the Apple Watch to be relatively accurate and easy to use. However, I have also noticed that the readings can sometimes vary, especially if the device is not positioned correctly on the wrist or if the user is not keeping their wrist still during the measurement process. It is always a good idea to consult with a healthcare professional if you have any concerns about your blood oxygen levels or if you are experiencing any symptoms that may require medical attention.

While the Apple Watch does have a blood oxygen sensor, it is important to understand its limitations and to use it as a general wellness tool rather than a medical diagnostic device.