alt Hacker Newsnon-invasive continuous blood sugar measurement is mired in patents and technical challenges. Turns out it's really difficult to disambiguate the absorption lines of glucose from other similarly shaped molecules when you're also dealing with untangling skin conductivity, transmissivity, sweat, inflammation etc.
I also think there's no financial incentive from incumbents to develop something like this. Why would abbott develop something that works "forever" if they can milk people buying new sensors every 10~14 days.