# Prototype smart ring cracks the holy grail of non-invasive blood sugar measurement

> A prototype smart ring developed by engineers at the University of California appears to have cracked one of the holy grails of health wearables: non-invasive blood sugar measurement.

- **Source:** [9to5Mac](https://9to5mac.com/2026/07/29/prototype-smart-ring-cracks-the-holy-grail-of-non-invasive-blood-sugar-measurement/?utm_source=gearopen.com&utm_medium=referral&utm_campaign=feed&utm_content=6a69ef06ac0af9a636c192bd)
- **Published:** 2026-07-29
- **Category:** Phones
- **Tags:** #iphone #apple #apple-watch
- **Canonical:** http://localhost:4321/a/6a69ef06ac0af9a636c192bd

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