A Continuous Glucose Monitor (CGM) is a wearable device that continuously tracks glucose levels. It provides a comprehensive view of blood sugar trends, offering more insight than traditional spot checks. This technology helps individuals, particularly those managing diabetes, understand how various factors influence their glucose.
What the CGM Sensor Is
The CGM sensor does not use a traditional hypodermic needle. Instead, it uses a tiny, flexible filament inserted just beneath the skin. This filament, made from a biocompatible material, is often coated with an enzyme like glucose oxidase. This enzyme reacts with glucose in the interstitial fluid to generate an electrical signal.
The flexible filament is extremely small, comparable to a thin toothbrush bristle. This design minimizes discomfort and allows for continuous data collection. While an applicator device uses a needle for insertion, it immediately retracts after placing the flexible sensor, ensuring no rigid needle stays under the skin.
Applying and Wearing a CGM Sensor
Applying a CGM sensor uses a specialized applicator device. Users select an appropriate body site, clean it with an alcohol wipe, and allow it to dry. The applicator is then pressed firmly against the skin, triggering the tiny sensor filament’s insertion.
Once inserted, the applicator is removed, leaving the sensor securely in place with an adhesive patch. Common wear sites include the back of the upper arm, abdomen, or upper buttocks. The adhesive patch keeps the sensor attached during daily activities like showering, exercising, and sleeping.
How CGM Technology Supports Health Management
A CGM continuously measures glucose levels in the interstitial fluid, the fluid surrounding the body’s cells. This data transmits wirelessly to a receiver, smartphone app, or insulin pump, providing real-time glucose readings every few minutes. This continuous monitoring offers a dynamic picture of glucose trends and patterns, including highs, lows, and how quickly levels are changing, a significant advantage over single-point fingerstick measurements.
Users can observe how diet, physical activity, stress, and medication impact their glucose levels, allowing for timely routine adjustments. For instance, the device provides trend arrows indicating if glucose is rising or falling rapidly, enabling proactive steps to prevent extreme highs or lows. This insight supports personalized care plans, leading to improved glucose control and a better understanding of individual metabolic responses.