The U.S. Food and Drug Administration has authorized the first wearable device capable of continuously monitoring both ketone levels and blood glucose, a milestone that could expand how patients with diabetes and people on ketogenic diets track their metabolic health. The agency announced the clearance on August 25, 2026, saying the device provides real-time data that previously required separate fingerstick tests or multiple sensors.
The FDA's authorization marks the first time a single wearable sensor has been cleared to measure both glucose and ketones continuously, according to the agency's press announcement. The device, whose manufacturer was not named in the initial release, is designed to transmit readings to a smartphone app or companion display, giving users a continuous picture of their metabolic state.
Traditionally, people with diabetes use continuous glucose monitors (CGMs) to track blood sugar, while ketone levels—markers of fat metabolism that can indicate diabetic ketoacidosis or dietary ketosis—are measured through fingerstick blood tests or urine strips. Combining both metrics in one wearable could reduce the burden on patients and help clinicians detect dangerous conditions earlier.
The FDA said the decision was based on clinical data demonstrating the device's accuracy and safety for its intended use. The authorization is likely to be classified under the agency's De Novo pathway, which creates a new regulatory category for low-to-moderate-risk devices with no existing predicate. The clearance covers over-the-counter use, meaning users may not need a prescription, though the agency has not yet detailed labeling requirements.
For people with type 1 diabetes, the ability to monitor ketones alongside glucose could be particularly significant. Rising ketone levels can signal the onset of diabetic ketoacidosis, a life-threatening complication that occurs when the body breaks down fat too rapidly. Continuous ketone data could provide an earlier warning than periodic fingerstick tests. For those using ketogenic diets to manage epilepsy, obesity, or athletic performance, the device offers a convenient way to confirm they are in nutritional ketosis without repeated blood draws.
However, experts caution that interstitial fluid measurements—the technique used by most wearable sensors—can lag behind blood values and may be less accurate at high ketone concentrations. The FDA's clearance does not mean the device is a replacement for laboratory tests, and users will likely be advised to confirm abnormal readings with traditional methods.
The announcement has generated significant discussion among clinicians and patients. Some see it as a step toward integrated metabolic monitoring, while others question cost, insurance coverage, and the potential for data overload. The FDA has not disclosed pricing, and it remains unclear whether private insurers or Medicare will reimburse the device outside of diabetes management.
This authorization arrives amid a growing market for wearable health sensors. Several companies have been developing multi-analyte devices, and this clearance may accelerate competition. The agency said it will continue to monitor the device's performance in real-world use and requires the manufacturer to report adverse events as they occur.
Analysis
Why This Matters
- The device combines two metabolic indicators in one wearable, potentially reducing the number of fingersticks and separate sensors patients must manage.
- Continuous ketone monitoring could improve early detection of diabetic ketoacidosis, a dangerous complication that is currently caught through periodic testing.
- FDA clearance may open a new regulatory pathway for multi-analyte wearables, setting a precedent for future devices that track additional biomarkers.
Background
Continuous glucose monitors have been commercially available for over two decades and are widely used by people with diabetes. Ketone testing, by contrast, has remained largely manual—requiring blood or urine samples—even though ketone levels are important for managing both diabetes and therapeutic ketogenic diets.
The FDA has gradually expanded its oversight of consumer health devices, creating the De Novo pathway in 1997 for novel low-risk technology. Over-the-counter CGMs were cleared in recent years, and the agency has signaled interest in supporting innovation in metabolic health. This new authorization builds on that trend, recognizing that a single sensor can measure multiple analytes from interstitial fluid.
Manufacturers have been working toward combined glucose-ketone sensors for years, but technical challenges—such as sensor drift and cross-reactivity between molecules—have slowed progress. The FDA's clearance suggests the developer overcame key accuracy hurdles, though the agency has not released full study results.
Key Perspectives
Patients with diabetes: Many see the combined sensor as a convenience and a safety improvement, particularly for those at risk of ketoacidosis. Fewer fingersticks and earlier warnings could improve quality of life.
Healthcare providers: Clinicians welcome the technology but emphasize the need for validation in diverse populations. They are concerned about patients self-managing based on device readings without medical supervision, especially if ketone levels rise into dangerous ranges.
Critics and skeptics: Some experts question the accuracy of interstitial ketone measurements, noting they may not correlate tightly with blood ketone values during rapid metabolic shifts. There are also concerns about cost, insurance gaps, and whether continuous data leads to anxiety or unnecessary dietary changes.
What to Watch
- Whether the manufacturer releases pricing and insurance coverage details, including whether Medicare will reimburse the device for diabetes patients.
- Publication of full clinical accuracy data, especially at high ketone ranges relevant to diabetic ketoacidosis.
- Regulatory responses from other agencies, such as the European Medicines Agency or Health Canada, and whether competitors file similar devices in the coming year.
- Real-world reports of sensor performance and adverse events, which the FDA has said it will monitor.