Using a Continuous Glucose Monitor for Type 2 Diabetes

Continuous glucose monitor (CGM)

Wondering if you can use a continuous glucose monitor for type 2 diabetes?  I don’t blame you, I love these little devices!

A few years ago, I worked in the wellness division of a hospital.  It was my team’s job to screen over 12,000 employees for their cholesterol and blood sugar levels.  This required getting what seemed like a half-pint of blood out of a finger stick, and we used pretty big lancets to do the job.

I stuck my own finger for the test, and I really hit a nerve!  This sounds whiny — not to mention a little nuts — but I’m not kidding when I say that I had little twinges of pain in that finger off and on for six weeks.

I can only imagine how torturous it must be for those of you who have to stick yourselves multiple times a day, every day.  Truly, I feel for you.  This brings me to why I love continuous glucose monitors, also known as CGMs!

How do continuous glucose monitors work?

CGMs consist of three main components, sensors, transmitters, and readers, or receivers.

CGM sensors

With CGMs, a very thin wire is inserted just under your skin.  The wire stays there for 10-14 days, depending on the brand of the device.  This wire is called a sensor because it “senses” the amount of sugar in your bloodstream.  The sensor is secured to your body with medical-grade tape.

CGM transmitters and receivers

A transmitter is then attached to the sensor.  The transmitter is the technology that takes the information from the sensor and communicates it to the device that lets you see your blood sugar levels.  You can read your blood sugar levels on a “receiver” or “reader” that comes included with your CGM.  Alternatively, you can read your blood sugar levels on your smartphone after downloading an app.

A continuous glucose monitor can help you lower your A1c

Of course, there’s the benefit of eliminating finger sticks.  But people who use CGMs are able to lower their A1cs because they get lots of information about how their bodies react to different foods and insulin doses.  They also get information not just about where their blood sugar levels are right now, but where their blood sugar levels are headed.  That makes a huge difference in their diabetes management.  If you know that your blood sugar is rapidly falling, you can eat something before you’re low.  That saves you from the miserable feeling of hypoglycemia and the time it takes to recover from that misery.

CGMs available in the US today

There are two main brands of CGMs available to people with diabetes in the US today:

  • Freestyle Libre is wearable for 14 days.  It does not require fingerstick calibration.  The Libre does require that the user wave the reader over the sensor in order to get a blood glucose measurement.  The Freestyle Libre does not come with built-in alarms to let you know if you’re running too high or too low.

  • Dexcom is wearable for 10 days, and it also does not require fingerstick calibration.  Dexcom checks your blood sugar every five minutes with no action required on your part, and it comes with a built-in alarm to let you know if your blood sugars are outside the range you set.

  • Medtronic and Senseonic also make continuous glucose monitors, but they both require two fingersticks a day, so I don’t recommend them.

The cost of continuous glucose monitors

Your insurance company may cover the cost of a CGM.  If you were to pay cash, these are the approximate costs:

  • Freestyle:  A one-time cost of $70-$100 for the reader, and about $125 a month for the sensors.

  • Dexcom:  Costco offers Dexcom discounts for members.  At this time, advertised fees are a one-time cost of $218 for the receiver, $318 for a 3-pack of sensors, and $146 for a transmitter, bringing the monthly cost after the purchase of the receiver to approximately $450.  Clearly, Dexcom is the more expensive option.

Who is a candidate for a CGM?

Medicare requires that a person meet these criteria before they will pay for a CGM:

  • have a diagnosis of diabetes, either type 1 or type 2

  • routinely monitor blood sugar at home at least four times a day

  • use 3 or more insulin injections per day OR be on an insulin pump

  • need frequent insulin adjustments based on blood sugar readings

Other insurance companies may have different criteria, but typically insurance companies follow the same criteria as Medicare when it comes to allowing costs.  If you want your insurance company to cover a CGM, you’ll need to check your policy to see if they have any particular requirements other than a doctor’s prescription.

Which continuous glucose monitor is best for me?

I strongly prefer the Dexcom because it continuously checks your blood sugar without you thinking about it and because it will alert you to highs and lows.  If you are asleep and your blood sugar dips down to a dangerously low 55, Dexcom will alarm to wake you up, and Freestyle won’t.  I think that’s critically important.

Having said that, any CGM is better than no CGM, so if your insurance company will only cover the Freestyle, then, by all means, take it!

The bottom line about continuous glucose monitors

If finger sticks don’t bother you but technology does, CGMs are not a good fit for you.  Consider a CGM if you’d love to stop sticking your fingers and your insurance will cover it.  If you’re afraid to go to bed at night because you’re not sure if your blood sugar will bottom out while you’re sleeping, Dexcom may help you get a good night’s rest.

Julie Cunningham is a Registered Dietitian and Certified Diabetes Care & Education Specialist. She believes food is the foundation of good health, and that our culture of obsession about body size is damaging to health, happiness, and productivity in far too many people. When not talking or writing about food and health, she can be found in the the mountains of western NC, where she lives with her family and four legged friends.

Julie Cunningham

How many carbs do YOU need?

Use my carb calcutor to get a personalized estimate of exactly how many carbs your body needs at each meal & snack in under one minute.

Yes, take me there now!

You may also like…

What Food Can Diabetics Eat Freely?

People with diabetes can freely eat foods with little to no carbohydrates. Meat and non-starchy vegetables contain little to no carbohydrates, and you can eat them without fear of raising your blood sugar. Download this list of 41 non-starchy vegetables that won’t raise your blood sugar and eat all you like!

read more


Submit a Comment

Your email address will not be published. Required fields are marked *