Pretty sure optical glucose is already a thing- it's just not very accurate yet.
Existing smart watches that claim to do this are basically garbage. Just use a random number generator instead.
Apple and Samsung are supposedly working on it: https://www.forbes.com/sites/davidphelan/2025/01/26/samsung-... But it seems to be hard and from what I have seen the new Galaxy Watch 8 won't have this feature.
Theres optical ones that can be built in a lab and require profiling to an individual. The most accurate ones are still invasive- just not consumable fungus extract based. Maybe some biomedical company makes a reference design.
I'm suggesting that it will change the world when it is an integrated part of something many/most of us buy and would eventually upgrade to.
You mean heart rate? they cleverly work by flooding your skin with the flash LED, and looking for small differences indicative of a heartbeat. Blood pressure is not something you can image with a consumer camera.