Continuous glucose monitors are also used by people who don't have diabetes. But what are the benefits?Image: Matt Harbicht/Getty Images ShareContinuous 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 dont have diabetes, or is it just a health fad?First, its important to understand how it works. When inserted on a persons arm, the monitors 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. Its actually life-changing, Dr. Michael (Mike) Natter, an endocrinologist at NYU Langone Health who has Type 1 diabetes, told Popular Science. Get the Popular Science newsletter Breakthroughs, discoveries, and DIY tips sent every weekday. By signing up you agree to our Terms of Service and Privacy Policy.Can it help to prevent diabetes?Type 2 diabetes doesnt happen overnight. Its 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 theres still time to turn things around. By making key lifestyle changeslike tweaking diet and exercisepeople 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 theres a catch: cost. At around $100 every two weeks, these devices may be out of reach for individuals at lower-income levelsthe very group most at risk.And then theres 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 moreleading 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 dietsbut the weight loss difference wasnt dramatic.Theres 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 ones 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 hasnt 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 theres a catchcorrelation doesnt 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 theyre 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, theres a big question mark: How should athletes interpret the data? Theres no clear consensus on what blood sugar levels are ideal for performance, and without well-defined guidelines, its hard to know how to use the information effectively.The bottom lineRight now, theres no solid evidence that continuous glucose monitors offer clear benefits for people without diabetes, said Dr. Natter.That doesnt mean they wont be useful in the futurebut the science isnt there yet. More research is needed to understand how this powerful technology can be used by non-diabetics, added Dr. Natter.