So the question is, what will be the secret behind this methodology? According to a report from 9to5Mac, they have speculated that there could be a couple of different methods to achieve this goal. The first would require the use of low-power radio waves which are sent through the human body, like the thumb, where there is adequate blood flow and the skin is thin enough to allow the radio waves to pass through.
The data is then sent back to the device and the characteristics of the blood is then analyzed. However, this begs the question of how will Apple implement this? If we had to guess, perhaps through the digital crown on the Apple Watch where users could easily place their thumb.
Another method that 9to5Mac discovered is based on a study posted on Nature in 2020. It suggests using a skin tag that can be easily and cheaply replaced. This tag will be taped to the skin and then energized through a device, like the Apple Watch, which will then take the readings and analyze it.
However, it should be noted that these are just some of the noninvasive methods that are currently known. Whether or not Apple will adopt them or come up with something of their own is a different story, but it could be a game-changer if such a feature were to be introduced in a commercially available product like the Apple Watch.