Garmin’s Quiet Bet on Blood Sugar Monitoring: A Patent That Could Reshape the Wearable Health Market

For years, the holy grail of wearable health technology has been a reliable, non-invasive way to measure blood glucose levels. Now, Garmin — a company better known for GPS devices and fitness watches — has quietly secured a patent that outlines a method for estimating blood sugar without breaking the skin. The implications for the wearable industry, the diabetes management market, and the broader health-tech sector could be enormous.

The patent, first reported by Android Authority, describes a system that uses optical sensors already common in modern smartwatches to estimate glucose concentrations in the blood. Rather than requiring a needle prick or an implanted continuous glucose monitor (CGM), Garmin’s approach would rely on light-based measurements taken from the wrist — the same general location where current wearables already track heart rate, blood oxygen saturation, and other biometrics.

What the Patent Actually Describes

According to the patent filing, Garmin’s system would use photoplethysmography (PPG) sensors — the green and infrared LED arrays found on the back of most fitness watches — to capture data about how light interacts with blood flowing beneath the skin. The patent details a method of analyzing the spectral characteristics of the reflected light to infer glucose levels. This is not a new concept in theory; researchers have been exploring optical glucose sensing for decades. What makes Garmin’s filing notable is the specificity of its signal processing approach and the fact that it comes from a company with the manufacturing scale and consumer distribution to actually bring such a product to market.

As Android Authority noted, the patent describes using multiple wavelengths of light and applying machine learning algorithms to improve the accuracy of glucose estimation over time. The system would reportedly calibrate itself using data from the wearer, potentially learning individual physiological patterns to refine its readings. This calibration step is significant because one of the major challenges in non-invasive glucose monitoring has always been accounting for the enormous variability in skin tone, tissue composition, hydration levels, and blood flow among different users.

A Race With No Clear Winner — Yet

Garmin is far from the only company pursuing this technology. Apple has reportedly spent over a decade and billions of dollars working on non-invasive glucose monitoring for the Apple Watch, a project that has been the subject of extensive reporting by Bloomberg and other outlets. Samsung has also signaled interest in the space, and a number of startups — including Rockley Photonics, which went public via SPAC before facing financial difficulties — have attempted to crack the problem with varying degrees of success.

The challenge is not merely technical but regulatory. The U.S. Food and Drug Administration classifies glucose monitors as medical devices, and any wearable that claims to measure blood sugar would need to undergo rigorous clinical validation before it could be marketed for that purpose. Even a feature positioned as an “estimation” or “trend indicator” rather than a diagnostic tool would likely face intense scrutiny, particularly given the potential consequences of inaccurate readings for people with diabetes who rely on glucose data to make insulin dosing decisions.

Why Garmin’s Position Is Unique

What makes Garmin a particularly interesting player in this space is the company’s existing credibility in the health and fitness wearable market. Unlike Apple, which sells a general-purpose consumer electronics device that happens to have health features, Garmin has built its smartwatch business around serious athletes, outdoor enthusiasts, and health-conscious consumers who are willing to pay premium prices for specialized functionality. The company’s Fenix, Forerunner, and Venu product lines already offer advanced health metrics including heart rate variability, pulse oximetry, body battery energy monitoring, and sleep tracking.

Adding glucose estimation to this portfolio would be a natural extension of Garmin’s strategy. The company has also been investing in its Garmin Connect platform, which aggregates health data from its devices and allows users to track trends over time. A glucose monitoring feature, even one that provided only directional estimates rather than precise milligram-per-deciliter readings, could be enormously valuable to the growing population of health-conscious consumers interested in metabolic health — a market that companies like Levels, Nutrisense, and January AI have been cultivating with CGM-based subscription services aimed at non-diabetic users.

The Metabolic Health Boom and Consumer Demand

The timing of Garmin’s patent is notable given the surging consumer interest in metabolic health. The popularity of GLP-1 receptor agonist drugs like Ozempic and Mounjaro has brought unprecedented public attention to blood sugar regulation, insulin sensitivity, and the relationship between glucose spikes and weight management. A wearable device that could provide even rough glucose trend data without the cost and discomfort of a CGM — which typically requires a small sensor inserted under the skin and replaced every 10 to 14 days — would tap into significant latent demand.

Current CGM systems from companies like Dexcom, Abbott (maker of the FreeStyle Libre), and Medtronic are primarily marketed to people with Type 1 and Type 2 diabetes, though the “wellness CGM” category has been growing. Abbott launched the Lingo brand in 2024, specifically targeting health-conscious consumers without diabetes. A non-invasive alternative built into a device people are already wearing could dramatically expand the addressable market — and potentially disrupt the CGM industry’s business model, which relies heavily on recurring sensor sales.

Technical Hurdles Remain Formidable

Industry experts have long cautioned that non-invasive optical glucose monitoring is one of the most difficult problems in biomedical engineering. Glucose is present in relatively low concentrations in the blood compared to other analytes, and its optical signature is easily overwhelmed by signals from water, hemoglobin, and other substances. Previous attempts by companies such as Google (through its now-defunct Verily glucose-sensing contact lens project) have failed to achieve the accuracy needed for clinical or even consumer use.

The fact that Garmin has filed a patent does not guarantee that the technology works well enough to ship in a consumer product. Companies routinely patent technologies that never make it to market, and the gap between a patent filing and a functional, accurate, FDA-cleared device can be measured in years — if the gap is ever closed at all. Garmin itself has not made any public announcements about plans to include glucose monitoring in upcoming products, and the company declined to comment on its patent filings when contacted by media outlets.

The Regulatory and Liability Minefield

Even if the technology proves accurate enough for consumer use, the regulatory path forward is uncertain. The FDA has been increasingly active in the wearable health space, issuing warning letters to companies making unsubstantiated health claims and establishing new frameworks for software as a medical device (SaMD). A glucose estimation feature that is marketed as a wellness tool rather than a medical device might avoid the most stringent regulatory requirements, but it would also need to be carefully positioned to avoid misleading consumers — particularly those with diabetes who might rely on it for clinical decision-making.

There is also the question of liability. If a consumer uses a wrist-based glucose estimate to make dietary or medication decisions and suffers harm as a result of an inaccurate reading, the legal exposure for the device manufacturer could be significant. This concern has reportedly been one of the factors slowing Apple’s entry into the space, and it would apply equally to Garmin or any other company attempting to bring a non-invasive glucose monitor to market.

What This Means for the Wearable Industry’s Next Chapter

Garmin’s patent filing is best understood not as an imminent product announcement but as a strategic signal. The company is investing intellectual property resources in a technology that, if it works, could differentiate its products in a crowded wearable market where competitors are increasingly offering similar feature sets. For an industry that has been searching for the next major health sensor to drive upgrade cycles — following the progression from step counting to heart rate monitoring to blood oxygen measurement to ECG capability — glucose monitoring represents the most commercially significant frontier.

The stakes are high. The global blood glucose monitoring market was valued at approximately $15 billion in 2023 and is projected to grow significantly over the next decade, driven by rising diabetes prevalence and expanding interest in metabolic health among the general population. Whichever company first delivers a credible, non-invasive glucose monitoring solution in a consumer wearable will capture enormous attention — and potentially enormous market share. Garmin’s patent suggests the company intends to be in that race, even if the finish line remains far from certain.

For now, the wearable industry watches and waits. The technology is promising. The demand is real. But the distance between a patent filing and a product on a consumer’s wrist is vast — and littered with the remains of previous attempts that never made it across.