Smart Clothes Now Track Your Blood Pressure

High blood pressure is commonly called a “silent killer” because it typically produces no obvious symptoms, allowing it to go unnoticed for extended periods. This poses a significant risk, as untreated hypertension can lead to serious conditions such as heart attack, stroke, or kidney disease. With nearly half of adults showing some level of elevated blood pressure, there is a clear need for better strategies to identify the condition early, enabling treatment before major complications arise.

Unfortunately, current methods for measuring blood pressure fall short of this need. The most widely used noninvasive tool, the pressure cuff, only provides occasional readings, which fail to capture the full picture since blood pressure fluctuates throughout the day. In addition, these devices tend to be somewhat bulky and inconvenient, making regular, frequent monitoring difficult.

But now, a better monitoring option appears to be on the horizon, thanks to the work of a group led by researchers at the National University of Singapore. They have created a battery-free sensor that is embedded into clothing to provide continuous blood pressure monitoring.

The system relies on ultra-thin epidermal sensors — flexible devices that adhere directly to the skin and track physiological signals in real time. Unlike conventional wearables, these sensors do not require onboard batteries. Instead, they are powered wirelessly through a specially engineered textile known as a metamaterial fabric, which is embedded into clothing. This fabric enables energy to be transmitted from a nearby smartphone to the sensors, eliminating the need for bulky power components.

To make this work, the system separates power delivery and data communication into two distinct frequency channels. Energy is transmitted at 13.56 MHz, while data is sent at 2.4 GHz, preventing interference between the two processes. This dual-channel approach allows the sensors to operate continuously while maintaining fast, reliable data transfer to a smartphone, which acts as both a power source and data hub.

In testing, the researchers demonstrated that the system could accurately measure systolic blood pressure not only at rest but also during physical activity. This is a significant advancement, as movement has traditionally posed challenges for wearable health monitors. Continuous monitoring during exercise provides a more comprehensive understanding of cardiovascular health, capturing fluctuations that would otherwise go unnoticed.

Beyond blood pressure, the technology could eventually be adapted to track a wider range of physiological signals, such as heart rate or sleep patterns. Its integration into everyday clothing also opens the door to more comfortable, unobtrusive health monitoring solutions.