CGM Breakthrough Opens New Markets for Sensor Technology

Best-selling author and diaTribe contributor Jim Hirsch shares his experience trying out the first over-the-counter CGMs to hit the market.
2024 was a breakthrough year for continuous glucose monitoring technology.
Abbott and Dexcom introduced new CGM devices for type 2 adults who do not use insulin or for adults who have pre-diabetes. Purchased over the counter, Abbott’s Lingo and Dexcom’s Stelo are trying to expand the market for CGM. The companies’ main CGM offerings, the Libre and the Dexcom G series, are primarily for people who use insulin, but there are only so many of us to go around.
Abbott and Dexcom believe that the Lingo and Stelo will appeal to anyone who wants to gain insight into their daily glucose journeys or metabolic health. In this sense, the products are part of the revolution in medical wearables that open a window into the human body and offer real-time information on the hidden truths of one’s heart rate, blood pressure, and many other essential metrics.
But I’m interested in diabetes, so to gain a better understanding of the Lingo and Stelo, I gave them a test run.
To be clear: I am not the target audience for these CGMs as I have type 1 diabetes, which means, of course, that I use insulin. I would also call myself a diabetes technology minimalist, as I have long used many of the diabetes devices but rarely take full advantage of them.
I’ll also cut to the chase: I believe both the Lingo and the Stelo are good products, and I commend both Abbott and Dexcom for advancing their technology so that it can benefit more people. But as I’ll explain, I doubt I could use either of these new CGMs even if I were part of their target audience.
Regardless of my own experiences, the more important question is this: Will the Lingo and Stelo replicate the wild success of the original CGM products?
A true believer in CGM
I am hardly unbiased about CGM. I’ve used Dexcom for many years, while my son uses the Libre, and my brother, Dr. Irl Hirsch, has prescribed both and is a long-time advocate for the devices. The technology isn’t perfect. “Signal losses,” in which the receiver doesn’t receive readings from the sensor, occur frequently, and my Dexcom G7, which I began using last year, rarely functions for the full 10 days. It dies after eight or nine days.
Nonetheless, CGM represents one of the most important breakthroughs in the history of diabetes. Its value is self-evident – it provides real-time glucose numbers on a continuous basis. Beyond that, CGM provides directional arrows that indicate if your blood sugar is steady, rising, or falling; and most importantly, the device alarms when you get too low. In my case, my Dexcom supports the automated insulin delivery (AID) system in my Tandem Control-IQ insulin pump so that my low blood sugars trigger alarms in both my phone and my pump. I call this hypoglycemia in surround sound.
Eliminating fears
The upshot is that CGM, if used properly, has effectively eliminated one of the most devastating fears in type 1 diabetes; namely, that a severe low can lead to disorientation, loss of consciousness, or even death. Talk to anyone who had type 1 diabetes before CGM was introduced, and that person can probably tell you about a hypoglycemic emergency that could have resulted in tragedy.
I could tell you about a couple of mine, but CGM has vanquished severe hypoglycemia from my life, which is why anyone who uses insulin should also be using CGM. (It’s also why CGM, according to the ADA and other medical societies, are considered the standard of care for people who use insulin.)
All of this is context for my use of Lingo and Stelo. My first impression is that they lack the single most important feature of the traditional CGM – hypoglycemic alarms. That is not a knock on these new products, as the alarms aren’t needed, but it makes the sales pitch more difficult. If the product is not a lifesaving device, is it worth the time and effort?
I bought my Lingo and Stelo online - $49 for one Lingo, and $105.19 for two Stelos. Abbott and Lingo refer to these products as “glucose biosensors,” whereas their traditional CGMs are just “sensors.” From my search online, it appears that a “biosensor” can jump through more subcutaneous hoops, or do more things, than a regular sensor. “Biosensor” also sounds more futuristic.

Different marketing approaches
The companies present their products differently. The Lingo website features a sexy young woman in a sleeveless top and long braided hair, wearing a sensor on her left arm. “Your body has the answers” is the seductive tagline. The product itself comes in a chic, dark blue box that seems well suited for expensive jewelry. The vibe is that this medical device will make you part of an upscale club.
The Stelo website features a young woman of color with a floral tattoo on her right arm, and a sensor is attached with a decorative overpatch. “Revolutionize your health” is the inspiring if not necessarily original tagline. The sensors come in a functional, nondescript purple box, and the logo is an arrow, which suggests a practical roadmap to better health.
Diabetes takes a back seat
The home pages for both products talk about nutrition or “glucose health,” but neither mentions the word “diabetes.” And that seems to be the point. Even if you have type 2 diabetes, neither product is about improving your diabetes management. Each is about improving your physical and emotional well-being.
The two sensors overlap in some basic ways. The Stelo is round, gray, and about the size of a quarter; the Lingo is white and a bit larger. They attach to your body pretty painlessly; they are similar in their wear periods (Lingo, 14 days; Stelo, 15 days) and their warmup times (Lingo, one hour; Stelo, 30 minutes). The Lingo refreshes its glucose reading every minute while the Stelo does so every 15 minutes (technically, they measure glucose readings in your interstitial fluid). I received the readings on my phone.
Interactive and personal
The Lingo and Stelo are also similar in their broader objectives. The products generate plenty of glycemic data, telling you – depending on the device – what time your glucose spiked, what your time in range was, and what your average daily glucose was. The products are interactive, educational, and personal, asking about your health goals and requesting data on your diet and exercise habits.
In one instance, Stelo sent me an email with a video attached, and the woman said that the device may give me an “aha!” moment with all this new information. “Glucose numbers are not good or bad. Think of them as powerful tools to help you understand your body.”
Stelo encouraged me to input information on “events” for food and exercise, which would then be overlaid graphically with blood sugar data. The company sent me videos on how to lower post-meal glucose spikes and how physical activity, sleep, and stress can all affect blood sugars. A good reminder: So much of diabetes education these days is done through videos.
A personal metabolic coach
Lingo seemed to offer even more data and personalization. In one of its videos, the company said the device “is your personal metabolic coach.” Lingo wants to identify your health goals, document your habits, customize your experiences, and provide coaching updates in real-time. One message told me that my “Lingo Count,” or blood sugar spike, was highest after breakfast, and it advised me that “morning food choices matter. Make your first meal savory, not sweet.”
I had not told Lingo that I exercise after breakfast, which is why I allow my blood sugar to spike. Lesson learned: If you don’t communicate with your device, you won’t get the full benefit. Lingo’s guidance is plentiful if not earth-shattering: Close the kitchen after dinner. Eat protein. Avoid alcohol. Stay hydrated.
Lingo’s brand name is fitting, as it has essentially created a whole other lingo. The “Lingo Count” translates glucose spikes into a single number, the goal being to hit a certain “Lingo Count” to “reduce your glucose exposure and improve your metabolic health.”
That’s a very different message than that given to people with type 1 diabetes, who are told to achieve certain A1C or time in range levels to reduce the risk of serious health complications. Neither Stelo nor Lingo wants to alarm its customers. It wants to coach them up, gently.
Glucose numbers vary
My one-time use of both devices reminded me that glucose technology, at best, is an approximation. I wore my Dexcom G7 while I wore the Stelo or Lingo, and I could crosscheck those numbers with my glucose meter. Comparisons were easy. One morning, after breakfast, my Stelo was 174 mg/dL, my G7 was 144 mg/dL, and my glucose meter was 205 mg/dL. After a four-mile run, my numbers were 129, 116, and 97 mg/dL, respectively.
Those numbers were in the ballpark, but at other times, the numbers varied more widely. In one instance, my G7 alarmed with a 64 mg/dL reading. But my Stelo was 93 mg/dL, and my glucose meter was 92 mg/dL. I had similar discrepancies with my G7 compared to my Lingo.
The lesson is, don’t bet the house on any one number. These are approximations, and whether your blood sugar is 110, 140, or 170 mg/dL probably doesn’t matter all that much in the long run. Blood sugars fluctuate constantly. You want to avoid the extremes and, particularly if you take insulin, you want to avoid extreme lows.
CGM devices dying early
Unfortunately, both my Stelo and Lingo died prematurely. Stelo petered out with seven days left, and Lingo stopped providing accurate readings with six days left. That was disappointing but not surprising. As noted, I have the exact same problem with the G7. Alas, I also had vexing “occlusion errors” with certain insulin pumps and was told I didn’t have the right “body type” for them (too much “lean muscle,” I was told). The Tandem is my fourth insulin pump.
Look, I’m grateful to all the medical device companies, as they have allowed me, as well as my son and countless others, to live much healthier lives. However, my aborted experiences with the Lingo and Stelo reminded me that the human body is too complicated, motley, and mysterious for any single medical device to work perfectly with every single body. One size does not fit all because we are all different sizes.
A glycemic odyssey
Nonetheless, I accept that I’m a protoplasmic aberration to the overwhelming success rate of all these products, and I understand why Abbott and Dexcom are excited about their new CGM devices. Wearable medical technology has become not only widely accepted but even trendy. And interest in glycemia is not just for people with type 2 diabetes or prediabetes. Many others, including elite athletes and fitness freaks, are taking an interest in their real-time blood sugar numbers.
But that doesn’t guarantee that the Lingo and Stelo will duplicate the adoption rates of the Libre and the G series. The stakes are different. If blood sugar numbers are not a matter of life and death – as they are for type 1 patients – then mortal vigilance is not required. Those of us who live our lives around our daily blood sugar numbers know the glycemic odyssey all too well. With the Lingo and Stelo, we will see who else wants to take that same journey.
Learn more about tips, tricks, and getting started with CGM here: