Blood sugar spikes and crashes aren’t just about feeling tired or hungry—they might hold the key to predicting diabetes risk early on, and without the need for frequent blood tests.
A team of researchers from the University of Tokyo has discovered a simple, noninvasive way to assess how well the body controls blood sugar using wearable technology. Their method could help doctors catch diabetes risk sooner and more accurately, using a painless approach.
This new research, published in Communications Medicine, takes advantage of continuous glucose monitoring (CGM), a technology that tracks blood sugar levels in real time throughout the day.
Unlike traditional tests—which rely on single blood samples taken during a doctor’s visit—CGM devices paint a full picture of how glucose levels rise and fall during everyday life, like after meals or during sleep.
Diabetes, especially type 2 diabetes, is often referred to as a “silent epidemic” because it can develop slowly without obvious symptoms. Catching early warning signs—like poor glucose regulation—is key to preventing or delaying the full onset of the disease.
But the problem is that standard tests, such as fasting glucose, the HbA1c blood test, or even the oral glucose tolerance test (OGTT), often miss these early stages. That’s because they provide only a snapshot rather than a continuous view of what’s happening in the body.
To tackle this, the Tokyo research team looked at data from 64 people who did not have diabetes. These participants wore CGM devices and also completed OGTTs and insulin sensitivity tests—some of the more intensive methods used in research and clinical settings to study blood sugar control.
The scientists focused on a CGM-based marker they called AC_Var, which reflects how much glucose levels fluctuate over time. They found that this measure closely matched the “disposition index,” a trusted predictor of future diabetes risk.
Not only did AC_Var prove to be a reliable indicator on its own, but when combined with another CGM metric—glucose standard deviation—the model outperformed all the traditional blood-based tests.
In other words, these two wearable-derived measurements did a better job at identifying people at risk of developing diabetes and even predicting complications like heart disease.
One of the most striking findings was that people whose blood sugar regulation was flagged as abnormal by this new method were often classified as “normal” by standard tests. That means many people with early-stage glucose issues may be slipping through the cracks under current testing practices.
To help make this technology more accessible, the team also developed a web-based tool. This app allows both individuals and health care providers to input CGM data and quickly calculate whether someone may have problems with glucose regulation—even if they haven’t been diagnosed with diabetes.
Professor Shinya Kuroda, one of the study’s lead authors, emphasized the potential impact of this approach. “By analyzing CGM data with our new algorithm, we identified individuals with impaired glycemic control—even when standard diagnostic tests classified them as ‘normal.’
This means we can potentially detect issues much earlier, creating an opportunity for preventive interventions before diabetes is diagnosed.”
Ultimately, the team hopes their findings will lead to easier, earlier detection of diabetes risk. With wearable devices becoming more common and affordable, this method could be widely adopted in routine health checks. It may also change how we think about glucose monitoring—not just as a tool for people who already have diabetes, but as a way to stop it before it starts.
If you care about diabetes, please read studies about the cooking connection between potatoes and diabetes, and low calorie diets may help reverse type 2 diabetes.
For more health information, please see recent studies about protein power: a new ally in diabetes management, and pineapple and diabetes: A sweet surprise.
The research findings can be found in Communications Medicine.
Copyright © 2025 Knowridge Science Report. All rights reserved.
