Why People with Type 1 Diabetes Need a Continuous Glucose Monitor

What is a continuous glucose monitor (CGM)?

CGMs are wearable devices that simplify glucosetracking.

They measure glucose in interstitial fluid continuously, providing updates every 1–15 minutes.

The data is sent to a transmitter and displayed on compatible devices for easy monitoring.

Four companies currently manufacture CGMs in the United States.

• Abbott (Freestyle Libre, Libre 2, and Libre 3)
• Dexcom (Dexcom G7)
• Medtronic (Guardian Connect and Guardian Sensor 3), and
• Senseonic’s Eversense.

What are the parts of a continuous glucose monitor?

CGMs have three key components:

1. Sensor

• A small wire catheter is placed under your skin, usually on your belly or arm.
• Held in place with adhesive tape.
• Measures glucose in the interstitial fluid under your skin.
• Needs replacing every 7–14 days, depending on the device.

2. Transmitter

• Sends glucose data wirelessly from the sensor to a display device.
• In some systems, the transmitter is built into the disposable sensor.

3. Receiver or smartphone

• Displays glucose data in real time on a handheld receiver, smartphone app, or insulin pump.
• Allows you to view real-time glucose levels, trends, and history.
• Data can be downloaded to a computer and shared with your healthcare provider.
• Some systems continuously send data for ongoing monitoring.

Why is a continuous glucose monitor great for diabetes self-management?

There are many reasons to consider using a CGM if you have type 1 diabetes.

• Real-time CGM monitoring has led to life-changing results, helping people avoid potentially dangerous complications.
• The Centers for Disease Control highlights regularglucosemonitoring as essential for managing type 1 diabetes. It helps you understand what affects your levels.
• A March 2024 study in JAMA Network Open found that CGMs can lower the risk of vision-related complications like diabetic retinopathy.
• CGMs are invaluable for managing diabetes. They help you track how different foods, times of day, activity levels and illnesses impact your glucose.
• CGMs aren’t just helpful for people with diabetes—they also benefit caregivers and loved ones involved in diabetes care.
• Finger-stick testing provides only limited snapshots, while CGMs deliver up to 288 readings daily for a full picture of glucose trends.

Here’s how CGMs offer life-changing advantages:

• Reduce or delay serious short- and long-term complications.
• Save money by improving diabetes management and reducing emergencies like hypoglycemia.
• Give detailed glucose data for better analysis by you and your healthcare team.
• Offer real-time biofeedback to help adjust diet or insulin doses, lowering risks of hypoglycemia and hyperglycemia.

Will I ever need to do a finger-stick test if I use a continuous glucose monitor?

• Some CGMs may require occasional finger-stick tests with a blood-glucose monitor to ensure accurate calibration.
• According to the Cleveland Clinic, finger-stick checks can offer reassurance if your CGM shows rising or falling numbers but you feel fine.
• They can also help clarify your glucose levels if you’re not feeling well, even when your CGM readings appear normal.

How much does a continuous glucose monitor cost?

• CGM devices can be expensive, but many insurance providers now cover them, helping make them more affordable.
• Be aware that your health insurance may only cover specific CGM models, and you’ll need to replace sensors and transmitters regularly.
• Check with your provider to see what devices and supplies are included in your plan.
• Additionally, many CGM companies offer resources to assist those who need financial help accessing these devices.

This content was made possible by Abbott, a Founding Partner of Beyond Type 1. Beyond Type 1 maintains editorial control over its content.