What is a Continuous Glucose Monitor (CGM) — and Why It Matters

For individuals living with diabetes, maintaining stable blood glucose levels is essential to prevent complications and improve overall health. Traditional glucose monitoring methods, such as fingerstick tests, have been standard practice for decades. However, advancements in technology have led to the rise of continuous glucose monitors (CGMs), which provide real-time data on glucose levels without the need for frequent pricking.

At Aidex CGM, we understand the importance of having access to the best tools for diabetes management. A continuous glucose monitor is one of the most valuable tools available to help you track your blood glucose levels, make informed decisions about insulin delivery, and adjust your lifestyle accordingly. In this article, we’ll highlight the best continuous glucose monitors available in 2025, along with their features, benefits, and how they can support you in managing diabetes more effectively.

Table of Contents

What is a Continuous Glucose Monitor (CGM)?

A continuous glucose monitor (CGM) is a device that tracks blood glucose levels in real time throughout the day and night. Unlike traditional methods that require fingerstick testing multiple times a day, a CGM uses a small sensor inserted under the skin to measure glucose levels in the interstitial fluid (the fluid surrounding your cells).

This sensor continuously transmits data to a receiver or smartphone app, providing you with up-to-the-minute information about your glucose levels. Some CGMs also have the capability to send alerts when glucose levels are too high or too low, allowing for quicker intervention and reducing the risk of dangerous spikes or drops in blood sugar.

CGMs are particularly beneficial for people with type 1 or type 2 diabetes who require insulin management, as they provide real-time glucose data to help make informed decisions about insulin delivery, meals, and activity levels.

Why Should You Use a Continuous Glucose Monitor?

While traditional blood glucose testing with fingersticks can provide useful information, CGMs offer several advantages, including:

Real-Time Glucose Data: CGMs continuously monitor glucose levels, providing immediate feedback on trends. This allows for quicker intervention when blood sugar is out of range, reducing the risk of complications.
Alerts and Alarms: Many CGMs come with customizable alerts that notify users when their glucose levels are too high or too low. This feature is especially helpful at night when you may not be aware of changes in your glucose levels.
Better Control: Continuous glucose monitoring helps you make more informed decisions about insulin dosing, meal planning, and exercise. By having a clearer picture of how your glucose levels fluctuate throughout the day, you can improve your blood sugar management.
Lifestyle Integration: CGMs are small, discreet, and easy to wear under clothing, making them a practical solution for everyday life. Whether you’re working, exercising, or attending social events, a CGM allows you to track your glucose levels without interruptions.

Top Continuous Glucose Monitors in 2025

There are several options for CGMs available in 2025, each offering unique features, accuracy, and ease of use. Below are some of the best continuous glucose monitors on the market:

1. Dexcom G7

Dexcom G7 is widely regarded as one of the most advanced CGMs available in 2025. Known for its accuracy, user-friendly design, and real-time data sharing capabilities, the Dexcom G7 is one of the leading choices for people with diabetes.

Key Features:

Accuracy: Provides highly accurate glucose readings with a minimal margin of error, making it one of the most reliable CGMs available.
Integration: Works seamlessly with insulin pumps and can be paired with smartphones and smartwatches for easy tracking.
Real-Time Data: Offers real-time glucose data every 5 minutes, allowing for immediate action if glucose levels are too high or low.
Convenience: The G7 sensor is easy to apply and lasts up to 10 days, with no need for fingerstick calibration.
Alerts and Alarms: Customizable alerts for high and low glucose levels, as well as trends over time.

Why It’s Great: The Dexcom G7 is a top choice for individuals who require high accuracy, advanced features, and easy integration with other diabetes management tools.

2. Abbott FreeStyle Libre 3

The Abbott FreeStyle Libre 3 is a popular and affordable option for continuous glucose monitoring. The system is known for its ease of use, slim design, and reliable performance, making it ideal for people who need a straightforward, effective CGM.

Key Features:

Compact and Discreet: The sensor is small and discreet, making it easy to wear under clothing without drawing attention.
Real-Time Monitoring: Provides glucose readings every minute, giving you near-continuous glucose monitoring throughout the day.
No Fingersticks Required: The FreeStyle Libre 3 eliminates the need for calibration with fingerstick tests.
Long Battery Life: The sensor lasts for 14 days, offering long-term monitoring with minimal maintenance.
Affordable: Generally more affordable than other CGMs, making it accessible to a wider range of users.

Why It’s Great: The FreeStyle Libre 3 offers an easy-to-use, low-cost option with reliable accuracy and the convenience of a long-lasting sensor.

3. Medtronic Guardian 4

The Medtronic Guardian 4 is another excellent choice for those seeking a reliable CGM with advanced features. Known for its integration with Medtronic insulin pumps, the Guardian 4 offers real-time glucose data and continuous feedback on blood sugar trends.

Key Features:

Accuracy: Offers accurate glucose readings, particularly for those who need detailed information to make insulin adjustments.
Integration: Works seamlessly with Medtronic insulin pumps, making it a great choice for those already using Medtronic technology.
Real-Time Monitoring: Continuous glucose readings are sent to the user’s smartphone or insulin pump, allowing for easy monitoring throughout the day.
Alert System: Provides customizable alerts for high and low glucose levels.
Sensor Life: The Guardian 4 sensor lasts for up to 7 days.

Why It’s Great: The Medtronic Guardian 4 is a solid option for individuals who require real-time glucose monitoring and are already using Medtronic insulin pumps.

4. Eversense CGM (Senseonics)

Eversense CGM stands out due to its unique long-term sensor wear, which lasts up to 180 days, significantly reducing the frequency of sensor changes.

Key Features:

Long Sensor Life: The sensor lasts up to 180 days, meaning you only need to replace it twice a year. This is ideal for users who don’t want to change sensors every few weeks.
Real-Time Glucose Data: The system provides real-time monitoring and alerts for high and low glucose levels.
Continuous Monitoring: Sends glucose readings to a smartphone app every five minutes, ensuring constant tracking.
Accuracy: Known for its reliable and accurate glucose readings.
Integration: Can be integrated with insulin pumps for advanced insulin delivery management.

Why It’s Great: The Eversense CGM offers the longest sensor wear available, making it perfect for those who prefer minimal sensor replacements throughout the year.

5. Senseonics Eversense XL

The Senseonics Eversense XL is an extended version of the standard Eversense CGM, offering longer sensor life, and is suited for individuals who need continuous monitoring for extended periods without frequent sensor changes.

Key Features:

Sensor Life: Provides up to 180 days of continuous glucose monitoring.
Alerts and Notifications: Sends real-time alerts directly to your phone for high and low glucose levels.
Sensor Accuracy: Reliable glucose readings, making it a great option for people with type 1 and type 2 diabetes.
Mobile Integration: Sends glucose data to a smartphone app for easy tracking and management.

Why It’s Great: The Eversense XL is perfect for users who want a CGM system with the longest sensor life and reliable monitoring.

How to Choose the Best CGM for You

Choosing the best continuous glucose monitor for your needs depends on several factors. Here are some things to consider:

Accuracy: Look for a CGM that offers the best accuracy, especially if you rely on the data for insulin adjustments.
Ease of Use: Consider how easy the device is to wear, apply, and maintain.
Integration with Other Devices: If you’re using an insulin pump or another diabetes management system, look for a CGM that integrates seamlessly with these tools.
Cost: Consider both the initial price and the cost of supplies (such as sensors and transmitters) when choosing your CGM.
Lifestyle Fit: Some CGMs require sensor replacements every 7-14 days, while others last longer. Choose a system that works with your routine and preferences.

At Aidex CGM, we can help you choose the best CGM for your lifestyle and health needs. Contact us to learn more about the latest continuous glucose monitors and how they can help you better manage your diabetes.

Conclusion

The best continuous glucose monitor can make a world of difference in diabetes management, offering real-time data, enhanced control, and the ability to adjust insulin delivery as needed. Whether you choose the Dexcom G7, Abbott FreeStyle Libre 3, or another system, having access to accurate, continuous glucose monitoring is essential for better blood sugar control and a more flexible lifestyle.

At Aidex CGM, we offer high-quality CGMs and expert guidance to help you make the best choice for your diabetes management needs. Explore our CGM systems today and take the next step toward better glucose control.