Researchers at UC San Diego have created CHARM, a prototype smart ring capable of non-invasively tracking glucose, ketones, and other biomarkers from sweat, potentially transforming health monitoring , though regulatory approval is still pending.
Researchers at the University of California, San Diego have developed CHARM, a prototype smart ring that could one day make glucose tracking far less intrusive by reading levels from sweat collected at the finger. Early tests compared the ring’s estimates with commercial continuous glucose monitors and blood glucose metres to see whether a wearable device of this kind could track changes through the day.
According to UC San Diego, the ring does not need exercise or heavy perspiration to work. A soft hydrogel inside the device passively draws small amounts of fluid from the skin, which then move through an internal channel to sensors that detect glucose. The system uses personalised calibration to translate sweat readings into estimated blood glucose levels, then sends the information to a phone. The current prototype runs for about 12 hours on a charge and keeps the sensing hardware and wireless electronics inside the ring itself.
Results published in Nature Communications suggested the device followed the same meal-related rises and falls seen in reference readings from healthy volunteers and people with type 1 diabetes. The researchers also reported that some sweat-based readings lagged behind blood measurements by about 15 to 20 minutes in individual tests, while calibration settings remained fairly stable for roughly two months.
The ring is designed to do more than track glucose. UC San Diego says it can also monitor ketones, while the sensor system can be configured for lactate and uric acid, as well as vitamin C and alcohol. The researchers say up to four biomarkers can be measured at once, and the data is sent wirelessly to a smartphone app. That puts CHARM ahead of consumer products that still rely on outside sensors, such as smart rings that pull glucose data from separate devices.
Even so, important hurdles remain before a product like this could become practical for everyday use. Accuracy during rapid glucose swings, how often the ring needs recalibrating, battery life and water resistance will all matter, particularly for people who need dependable readings throughout the day. CHARM remains a research prototype and is not commercially available. FDA guidance says no smartwatch or smart ring has been authorised, cleared or approved to independently measure or estimate blood glucose without piercing the skin, so anyone using glucose readings for treatment decisions should continue relying on an FDA-authorised monitor.
Disclaimer: This content is for informational purposes only and is not intended to be a substitute for professional medical judgment, advice, diagnosis, or treatment.
