In March 2024, the U.S. Food and Drug Administration cleared the first over-the-counter continuous glucose monitor, Dexcom's Stelo, describing it as intended for adults who do not use insulin — including "those without diabetes who want to better understand how diet and exercise may impact blood sugar levels" [source: FDA, 2024]. Three months later, Abbott received clearance for two more OTC monitors, one of them, Lingo, aimed squarely at "general consumers looking to improve their overall health and wellness" [source: Abbott, 2024]. Almost overnight, a medical device built for diabetes became a wellness gadget you could buy without a prescription.
Then, in August 2026, a review in JAMA Internal Medicine landed with a blunt conclusion: there is no scientific evidence that continuous glucose monitoring improves health or prevents disease in people without diabetes [source: JAMA Internal Medicine, 2026]. So which is it — the next frontier of personalized health, or a solution in search of a problem? The honest answer requires separating three things that marketing tends to blur: what a monitor actually measures, what those measurements mean for a healthy body, and what has actually been proven versus merely claimed.
Why glucose monitors are suddenly on healthy arms
A continuous glucose monitor is a coin-sized patch with a tiny filament under the skin that samples glucose in the fluid between cells, sending a reading to a phone every few minutes. For decades this was prescription technology for people with diabetes, especially those on insulin, for whom a missed high or low can be dangerous. The 2024 over-the-counter clearances changed the audience overnight. Stelo is worn up to 15 days and reports a new reading every 15 minutes [source: FDA, 2024]; Abbott's Lingo is worn up to 14 days, built on the FreeStyle Libre platform the company says is already used by around six million people worldwide [source: Abbott, 2024].
Crucially, the FDA's own language frames these as tools to "understand how diet and exercise may impact blood sugar" — an intended use, not a claim that wearing one makes you healthier [source: FDA, 2024]. That distinction is where the wellness industry has rushed in. The monitors have been folded into a broader "metabolic health" and biohacking movement, and into the apps that surround it.
Integration is the growth story. In late 2024 Dexcom partnered with the smart-ring maker Oura, and the Oura app now displays Stelo glucose data alongside sleep, stress, and activity, next to an AI feature called Meals that estimates nutrition from a photo of your plate [source: Oura, 2025]. The monitors have also been pulled into the weight-loss economy: in August 2025 the FDA cleared Signos, a CGM-powered weight-management app that runs on Stelo sensors and markets support for people taking GLP-1 drugs [source: FierceBiotech, 2025]. Abbott, for its part, publishes guidance arguing that a monitor lets GLP-1 users see how the medication "blunts post-meal spikes" [source: Abbott, 2025]. None of that integration is evidence of benefit; it is distribution. But it explains why healthy people are suddenly wearing a device designed for a disease they don't have.
What the number on the screen actually is
To weigh any of this, you have to know what the device measures — and what it doesn't. A CGM does not read blood glucose directly. It measures glucose in interstitial fluid, which lags behind blood by several minutes and is estimated, not counted, by an algorithm. Every sensor therefore carries a margin of error, and reviewers caution that a single reading is better understood as a range than a precise figure [source: Diabetic Medicine, 2024]. For someone with diabetes deciding on insulin, that approximation is still far better than flying blind. For a metabolically healthy person parsing a wiggle on a graph, the same imprecision can turn ordinary noise into a false alarm.
There is a deeper measurement problem that surfaced in a 2025 study from Mass General Brigham. Researchers compared CGM readings against HbA1c — the blood test that reflects average glucose control over months — in 972 adults. In people with diabetes, the two tracked closely. But the correlation weakened in prediabetes and essentially vanished in people with normal blood sugar [source: Diabetes Technology & Therapeutics, 2025]. As the lead author put it, CGM data "is not a substitute for HbA1c" [source: Diabetes Technology & Therapeutics, 2025]. In other words, for a healthy person, the dramatic real-time curve on the app may say very little about long-term metabolic health at all.
What a "spike" does and doesn't mean
The single most misunderstood thing a monitor shows is the "spike." Eat a bowl of rice, watch the line jump, and an app may flag it in alarming red. But glucose rising after a meal is normal physiology that happens in everyone — the body releases insulin, the number comes back down. Standard clinical thresholds treat a fasting level under 100 mg/dL (5.6 mmol/L) as normal, and a reading under 140 mg/dL (7.8 mmol/L) two hours after a glucose load as normal as well [source: American Diabetes Association, 2025]. A transient post-meal rise inside those bounds is not disease; it is a healthy body doing its job.
This is where measurement and meaning come apart. The monitor is measuring something real, but the interpretation layered on top — that spikes are inherently harmful, that a flatter curve is a healthier one, that you should rearrange your diet to suppress every rise — is not something the number itself establishes. Much of the "glucose optimization" advice circulating online treats a normal excursion as a problem to be engineered away, without evidence that doing so benefits a person who is not diabetic.
The science that wellness brands cite most often actually illustrates the gap. A landmark 2015 study from the Weizmann Institute monitored 800 people across roughly 47,000 meals and found that individuals eating identical foods had strikingly different glucose responses [source: Cell, 2015]. That finding is real and genuinely interesting — it is the basis for the pitch that generic diet advice is wrong for you. But notice what it shows: that responses vary between people, not that measuring your own response and chasing a flatter line makes you healthier. The leap from "your curve is personal" to "flattening your curve improves your health" is exactly the inference the evidence has not made.
The evidence for healthy users, weighed honestly
So what does the outcome evidence say? For people without diabetes, it is thin, and where it exists it is unimpressive. The 2026 JAMA Internal Medicine review, led by researchers at the University of Gothenburg, surveyed the field and concluded there was no scientific evidence that CGMs improve health or prevent disease in people who do not have diabetes, and warned that marketing has outpaced the data [source: JAMA Internal Medicine, 2026]. Systematic reviews of CGMs as a behavior-change tool in people without diabetes have similarly found the evidence limited and mixed rather than compelling [source: Diabetic Medicine, 2024].
This does not mean a monitor can never be interesting or motivating for a curious person; seeing a number move can prompt a walk after dinner. It means the strong version of the claim — that continuous monitoring delivers a measurable health benefit to the metabolically healthy — is not supported. And it matters that the professional guidelines reflect this. The American Diabetes Association recommends CGM within diabetes care, most strongly for people using insulin; no major guideline recommends routine monitoring for healthy people as a wellness practice [source: American Diabetes Association, 2025]. The evidence base that makes CGMs genuinely valuable lives in the disease they were designed for.
The case for caution
There is also a plausible downside, and it is not hypothetical. A 2024 narrative review in Diabetic Medicine examined CGM use by people without diabetes and flagged a real risk: that watching glucose all day can breed anxiety about what "normal" even is, drive obsessive food tracking, and in some people tip into disordered eating, including orthorexia — an unhealthy fixation on "clean" or "pure" foods [source: Diabetic Medicine, 2024]. When a device paints every meal green or red, food stops being food and becomes a test to pass or fail.
That risk compounds the measurement problem. A reading that is imprecise by design, interpreted through the belief that every spike is dangerous, in a body where spikes are normal, is a recipe for chasing noise. The same review urged clinicians to be cautious interpreting CGM readouts in people without diagnosed diabetes, precisely because the significance of those readings is so poorly established [source: Diabetic Medicine, 2024]. Data without context is not insight; it can be the opposite.
Marketing claims versus verified facts
The last layer to keep straight is evidentiary status — who is telling you a monitor helps, and on what basis. An FDA clearance means a device is safe and performs as described; it is not a verdict that the device improves the health of a healthy user [source: FDA, 2024]. A company page explaining how a monitor pairs with a GLP-1 program is marketing, however reasonable it sounds [source: Abbott, 2025]. A partnership that puts glucose data next to your sleep score is a product feature, not a clinical finding [source: Oura, 2025]. And a peer-reviewed review in JAMA Internal Medicine concluding there is no evidence of benefit is a different kind of statement altogether [source: JAMA Internal Medicine, 2026].
Blur those together and "the FDA cleared it," "a study monitored 800 people," and "it improves your metabolic health" collapse into one vague impression of scientific endorsement. Pulled apart, the picture is clearer: the devices are real, well-made, and legitimately useful for diabetes; the wellness use is a marketing frontier that the outcome evidence has not yet caught up to.
What to watch
The honest read in 2026 is neither "everyone should track their glucose" nor "it's all snake oil." Continuous monitors are a genuine advance for diabetes and a fascinating window into individual physiology. For people without diabetes, they are an intriguing measurement in search of a proven meaning — and, used with the belief that every rise is a threat, a plausible source of needless worry.
Three things will tell you whether that changes. First, whether randomized trials — not app testimonials — show that monitoring produces lasting health benefits in people without diabetes. Second, whether anyone learns to interpret these readings in healthy bodies well enough to separate a meaningful signal from normal noise. Third, whether professional guidelines ever move beyond diabetes to endorse wellness monitoring. Until then, the useful posture is the one the evidence supports: take the measurement seriously, hold the meaning lightly, and remember that a monitor tells you what your glucose is doing, not what it means.