Over-the-Counter CGMs: Dexcom Stelo, Abbott Lingo and the Glucose Data Market for People Without Diabetes

Short answer: since 2024, anyone in the US over 18 and not on insulin can buy a continuous glucose monitor without a prescription, and two products dominate: Dexcom’s Stelo and Abbott’s Lingo.

That changed a medical device into a consumer one. The market it sells into is large: about 97.6 million US adults have prediabetes, 38% of adults, and 38.4 million people have diabetes, about a fifth of them undiagnosed [1]. On top of that sits the population on GLP-1 drugs, who want feedback on what they eat.

For companies building nutrition, metabolic, weight-loss or coaching products, the questions are practical. What is each device cleared for? What does “normal” look like on a CGM? What does the evidence actually support for people without diabetes? And how does glucose data get from the sensor into your product, and how late? The last one surprises most developers.

What is cleared, and for whom?

Two details matter for product teams.

Both consumer ranges are capped. Stelo’s app shows glucose between 70 and 250 mg/dL and reports anything outside as below 70 or above 250, even though the sensor measures a wider range [16]. Lingo shows 55 to 200 mg/dL [6]. That is appropriate for wellness products, and it means neither is a source for detecting true hypoglycemia or severe hyperglycemia.

None of these is for people on insulin. Insulin users need prescription CGMs such as Dexcom G7 or FreeStyle Libre, with wider ranges and alarms.

How big is the over-the-counter CGM market?

Early numbers were modest. Dexcom launched Stelo in August 2024 and reported about 140,000 users and $22 million of Stelo revenue by the end of 2024, below analyst expectations [8]. Dexcom as a whole expects $5.18 billion to $5.25 billion of revenue in 2026, and cites Stelo’s rollout as one growth driver [9].

The strategy has shifted from sensor to software. In the second quarter of 2026 Dexcom launched a fully redesigned Stelo app with AI-driven insights and better food logging [9]. It also reported results from its CONNECT trial showing CGM use improved glucose control in people with type 2 diabetes not on insulin [9], the population that sits between a prescription device and a wellness one.

The distribution strategy runs through partners. Dexcom invested $75 million in Oura in November 2024, and in May 2025 Oura launched a Glucose feature that shows Stelo readings alongside sleep, activity and stress, plus AI meal logging from photos. Stelo can be bought through Oura for $99 in the US [10]. That makes the smart ring market leader one of the main storefronts for a CGM.

What does normal glucose look like on a CGM?

This is the question every consumer CGM user asks in week one, and the answer is calmer than most social media suggests.

In a multicenter study, 153 healthy, non-obese children and adults wore a blinded Dexcom G6 for up to 10 days [11]:

• Average glucose was 98 to 99 mg/dL in every age group except over-60s, at 104 mg/dL.
• The median participant spent 96% of the day between 70 and 140 mg/dL.
• About 2.1% of the day, roughly 30 minutes, above 140, and about 1.1%, roughly 15 minutes, below 70.
• Within-person variability, measured as the coefficient of variation, averaged 17%.

So a reading of 150 after a meal is normal. A day with several hours above 140 is not.

The more interesting research is on variation between people. Using CGMs on standardized meals, Hall and colleagues found that people classed as normoglycemic by standard tests still reached prediabetic ranges about 15% of the time and diabetic ranges about 2%, and that responses to identical meals varied widely between individuals [12]. That is the scientific case for consumer CGMs: glucose response is personal, and a single fasting test or HbA1c does not show it.

How does CGM data reach your product?

Stelo writes glucose to Apple Health and to Health Connect. In Apple Health, readings arrive on a three-hour delay, while the Stelo app shows them in near real time [13]. Stelo also connects to the Oura app [10]. It is not listed among the devices supported by the Dexcom API [14].

Lingo writes glucose readings to Apple Health, labelled as glucose from interstitial fluid rather than blood glucose, and reads workouts from it. Abbott lists Health Connect support on Android too [5].

Dexcom’s prescription CGMs (G6, G7, G7 15-day, ONE, ONE+) share glucose to Apple Health and Health Connect on a three-hour delay [15]. They are also available through the Dexcom API, an OAuth cloud API for approved partners, where data from the mobile apps arrives with a one-hour delay in the US and three hours elsewhere [14].

FreeStyle Libre apps do not write readings to Apple Health or Health Connect themselves, based on our own review of the apps; readings reach the platform stores only through third-party bridge apps. Abbott does not offer a public developer API.

Three consequences follow for anyone building on glucose data.

• Real-time meal feedback needs the vendor’s own app. Anything reading from Apple Health, Health Connect or the Dexcom API sees glucose one to three hours late. That is fine for daily trends, time in range and after-the-fact meal responses. It is not fine for “you’re spiking now”. The broader mechanics are in why wearable data arrives late.
• Expect duplicates. A Stelo user connected through both Oura and Apple Health can produce the same readings twice. Pick one source per user and per data type; the method is in deduplicating health data across wearables.
• Respect each device’s range. Stelo reports only 70 to 250 mg/dL and Lingo 55 to 200 mg/dL [6][16]. Do not build low or high alerts that assume either can see beyond that.

What should a product show?

• Time in range, not spikes. The share of the day between 70 and 140 mg/dL is the most stable summary for people without diabetes, and the healthy reference is about 96% [11]. Individual post-meal peaks above 140 are normal and short.
• Personal meal responses, after the fact. Pair logged meals with glucose readings from the following two hours. Given the delay from the platform stores, present this as a review, not a live alert.
• Stay on the wellness side. Lingo’s own listing says it is not intended to diagnose any disease [5]. A product that tells a user they “may have diabetes” from CGM data is making a disease claim; see whether your health app is a medical device.
• Keep the individual readings. A daily average of a CGM stream hides exactly the variation that makes a CGM worth wearing.

The short version

Stelo and Lingo made CGMs a consumer product in 2024: for adults not on insulin, about $90 to $100 a month, 14 to 15 days per sensor [2][3][4]. Adoption started slowly and is now being pushed through software and partners such as Oura [8][9][10]. Healthy people spend about 96% of the day between 70 and 140 mg/dL, and short peaks after meals are normal [11]; glucose response varies a lot between people [12], but outcome evidence for CGMs in people without diabetes does not exist yet. For builders, the hidden constraint is timing: glucose reaches Apple Health, Health Connect and the Dexcom API one to three hours late [13][14][15], Stelo is not in the Dexcom API, and Libre apps do not write to the platform stores at all.