Does wearing a continuous glucose monitor help people without diabetes? We asked experts.

Continuous glucose monitors were originally designed to help people with diabetes track and better manage their blood sugar (aka ‘blood glucose’). Nowadays, not everyone you see wearing one actually has diabetes. In fact, nearly 1 in 5 people use the device for other reasons, according to a new study. But is a continuous glucose monitor really useful if you don’t have diabetes, or is it just a health fad?

First, it’s important to understand how it works. When inserted on a person’s arm, the monitor’s tiny platinum sensor sits in the interstitial fluid (the fluid between cells) just beneath the skin. Attached to the sensor is a small transmitter that sends data on blood sugar levels to a smartphone or receiver. 

Unlike traditional fingerstick tests, continuous glucose monitors provide continuous readings throughout the day and night, offering a real-time picture of blood sugar levels and helping people with diabetes better manage their condition. They also eliminate the inconvenience and pain associated with frequent fingerstick tests. “It’s actually life-changing,” Dr. Michael (Mike) Natter, an endocrinologist at NYU Langone Health who has Type 1 diabetes, told Popular Science.

Can it help to prevent diabetes?

Type 2 diabetes doesn’t happen overnight. It’s the result of the body struggling to regulate sugar, its main source of fuel. This process usually breaks down gradually, often long before any symptoms appear. In fact, chronically high blood sugar can be an early warning sign that something is off.

“Elevations of blood glucose after meals can predict pre-diabetes or diabetes more accurately than Hemoglobin Ac [a traditional diabetes biomarker] in some people,” explained Dr. David Klonoff, clinical professor of medicine at UC San Francisco and president of the Diabetes Technology Society. This is a big deal because catching the issue early means there’s still time to turn things around. By making key lifestyle changes—like tweaking diet and exercise—people at risk can delay or even prevent diabetes entirely.

Could continuous glucose monitors be the key to catching high blood sugar before it spirals into diabetes? Dr. Natter thinks they have potential, but there’s a catch: cost. At around $100 every two weeks, these devices may be out of reach for individuals at lower-income levels—the very group most at risk.

And then there’s the issue of interpreting the data. A study of 8,315 nondiabetic adults (aged 40 to 70) found that blood sugar levels fluctuate greatly from day to day, making continuous glucose monitor data tricky to interpret without proper context. When people misinterpret their blood sugar trends, this leads to a lot of unnecessary anxiety and stress, said Dr. Natter.

Can it help with weight loss?

A continuous glucose monitor allows you to see how your body reacts to different foods and physical activity. Eat a carb-heavy meal? Watch your blood sugar spike. Go for a run? See it drop. The idea is that this real-time feedback nudges users to cut back on carbs and move more—leading to weight loss.

But do continuous glucose monitors actually aid in weight loss? So far, the evidence is limited.

In a small 2022 study, 40 overweight adults without diabetes were split into two groups: one received standard dietary advice, while the other got the same advice plus a continuous glucose monitor. After eight weeks, those wearing glucose monitors lost an average of 3.1 kg, compared to 2.3 kg in the other group. The results suggest that continuous glucose monitors might help people improve their diets—but the weight loss difference wasn’t dramatic.

There’s also a downside: too much data without the right context can do more harm than good.

When people are overwhelmed with data and given no guidance on how to interpret it, “there is a high risk for demonizing certain otherwise healthy foods,” warned Dr. Natter, who is concerned that this could contribute to the rise of disordered eating. “A good example of this is that certain fruits, like grapes, may ‘spike’ one’s blood sugar, but what is important to understand is that a mild spike in glucose is normal (up to ~140mg/dL) and expected after ingesting certain carbohydrates.” 

Can it help to prevent health problems?

Not everyone reacts to food the same way. Two people could eat the same meal, yet their blood sugar levels can spike differently. Continuous glucose monitors reveal these personal patterns, helping non-diabetics fine-tune their diets for better metabolic health, explained Dr. David Klonoff. 

The idea is that fewer blood sugar spikes might mean a lower risk of long-term health issues. But does stabilizing your blood sugar actually prevent disease? Science hasn’t delivered a definitive answer yet.

Some research suggests that prolonged high blood sugar in non-diabetics is linked to a greater risk of cardiovascular problems. But there’s a catch—correlation doesn’t mean causation. While researchers have observed this association, no study has proven that blood sugar spikes directly cause heart disease.

So while continuous glucose monitors might offer valuable insights, whether they truly help prevent major health problems remains an open question. 

Can it help to improve athletic performance?

For athletes with diabetes, continuous glucose monitors are game-changers, helping them avoid dangerous blood sugar crashes during intense workouts. But now, some athletes without diabetes are strapping them on, hoping to fine-tune their fueling strategies and push their performance to the next level.

“Some elite athletes will wear a CGM to identify if they’re becoming hypoglycemic and that it is time for carbohydrate intake to maintain peak metabolic performance,” explains Dr. David Klonoff.

Early research hints at potential benefits. A study of seven ultramarathon runners found that higher blood sugar levels were linked to faster running speeds, and those who consumed more energy and carbohydrates tended to perform better overall. This suggests that continuous glucose monitors might help endurance athletes optimize carb intake for sustained energy.

But before CGMs become a must-have training tool, there’s a big question mark: How should athletes interpret the data? There’s no clear consensus on what blood sugar levels are ideal for performance, and without well-defined guidelines, it’s hard to know how to use the information effectively.

The bottom line

Right now, there’s no solid evidence that continuous glucose monitors offer clear benefits for people without diabetes, said Dr. Natter.

That doesn’t mean they won’t be useful in the future—but the science isn’t there yet. More research is needed to understand how this powerful technology can be used by non-diabetics, added Dr. Natter.

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