Can you a new bucket in the Connect app, under the Health Stats so we can track blood sugar in the blood? will be a manual record, similar to the weight and blood pressure.
I don't see that happening any time soon, but you can always request such features here - Share Ideas | Garmin
similar to the weight and blood pressure.
There are associated Garmin devices for these metrics. I don't believe blood pressure was an option until they came out with the Garmin Index BPM.