
Continuous Glucose Monitors. For those of us with shiny object syndrome, it seems like it is a must have gadget, but is it? Do you really need a CGM? We thought it was important to look at the benefits and the drawbacks of using a continuous glucose monitor with your diabetes.
What is a Continuous Glucose Monitor?
A Continuous Glucose Monitor is a small device worn under the skin that uses interstitial fluid to monitor blood glucose levels. It then transmits readings to a receiver and allows a person with diabetes to have a guide to what blood glucose levels may be at a given time and whether they are expected to rise or fall in the near future.
What are the benefits of using a CGM?

More data
The biggest benefit by far is the fact that you always have data on hand. This data allows you to be proactive with your care. You can stop a high or a low before it interferes with your activities.
I love my CGM for its convenience. I am busy with work during day where I don’t get much time, with a CGM I can monitor my blood sugars more closely.
Less finger sticks.
Modern CGMs require fewer or even no finger sticks. This is a huge benefit to many.
Finger sticks are always suggested if the readings on the CGM do not seem in keeping with current symptoms. If you feel low and your CGM says you are in range, double check with a finger stick. The same if you are high.
I love love that you don’t have to prick your finger as much!
Less equipment to carry
When using a CGM, you no longer must carry test strips, a glucometer, and lancing device. You now have a sensor that is on your body and can read your blood glucose levels on a phone, smart watch, or receiver.
Being able to have my BG reading at my fingertips and not having to carry around a machine, strips etc. and then having to prick my finger has been a game changer.
Ease of use
Continuous Glucose Monitors today require very little training. Most users find that that once their sensors are working, they are able to forget about their diabetes for a few minutes and still know that they are safe.
I love that my CGM is always checking in the background — it’s one less thing for me to remember to do.
Peace of mind
Adults living with diabetes love the fact that they have a machine always looking out for them. It allows them to no longer fear going low without noticing. A CGM also gives many people with diabetes comfort that they will be alert if they go low while they sleep.
I like that I don’t have to remember to check my blood sugars at regular intervals, the data is just there when I need it! Also, it gives me insight into what my blood sugars are doing overnight without having to set multiple alarms.
Lower A1c
Many people with diabetes feel that the ability to have data, the check readings more often and be proactive with their care has helped them to increase their time in range and decrease their A1c.
I use a CGM and have had my best A1C’s in conjunction with my pump. I could not achieve this without the two.
Data sharing
Whether you are a parent of a child with diabetes or an adult with diabetes who lives alone, data sharing can be a huge lifesaver. Data sharing allows close friends or family members to see your blood sugar readings. If you fall asleep and your readings drop without you waking, they can contact you or call 911 on your behalf.
What are the benefits of a CGM for parents of children with diabetes?
A recent study by Dr. Molly L. Tanenbaum, PhD found that parents of children with diabetes feel that the benefits of a CGM far outweigh any drawbacks. Her study found that participants felt that the CGM:
- decreased stress
- provided useful data
- resulted in fewer finger sticks for their child
- gave them peace of mind and better rest at night.
- allows them to give their children more freedom with the knowledge that they are safe
Being able to monitor my daughter’s numbers from my phone makes it easier to let her go to play dates and afford her freedom to do every day kid activities without me being present.
What are the drawbacks of using a CGM?

Cost
The biggest drawback of using a Continuous Glucose Monitor is cost. If you do not have private insurance that covers the full cost of a CGM, it can be an added expense that may or may not be worth it to you.
The additional site piece is a small price to pay for the safety it provides, and improved quality of life. But the cost makes it unattainable for most people and that is not at all fair!
Wearing another device
For some people, the idea of being attached to something 24/7 can make the idea of using a Continuous Glucose Monitor unattractive. They may already be using an insulin pump, and just not want to wear something else.
Depending on body size and issues of hypotrophy, there can also be an issue of having very limited places on the body to put devices.
They aren’t perfect
Despite the best efforts of the companies making CGMs, they are not perfect. There will be errors in accuracy, some sensors will fail, you may experience what art known as compression lows, and sometimes you may lose communication.
The downside of using a CGM is the loss of connectivity and compression lows.
They get caught on things
While many people will add tape to their sensors, just like infusion sets, Continuous Glucose sensors can be torn out much to the dismay of users and their bank accounts.
I greatly dislike how they have a tendency to easily snag on things and tear off. Which is always followed by a really annoying customer service call.
Data overload
While a CGM can offer trends and information on where blood glucose levels are during the day or night, a person can easily be caught up in the data. It can become overwhelming as you see rises and falls. This can sometimes lead to increased stress and burnout. It is important to use trends and information as guides and not be caught up in watching the data constantly.
At first it was overwhelming — I spent too much time looking at and reacting to my numbers. It took me a while to find the right amount of attention to give it.
Alarm Fatigue
Some people become annoyed by the constant alerts of highs, lows, trends, and errors that can be set on their CGM.
Inability to understand the data
If you do not have a good knowledge of how your insulin works or how to make adjustments, a CGM can be overwhelming.
However, if you don’t have this knowledge, you should be able to work with your diabetes care team to help you gain the knowledge you need to interpret what is going on with blood sugar levels and trends. They will be able to guide you on how to adjust insulin levels or activity to create more time in range.
Issues with adhesives
As with any site, some people will have issues with the adhesive. There could be an issue with the adhesive of the CGM. It could be removing it or having it not stick properly.
There are many coverings and options that can help you to overcome this obstacle if you decide that a CGM is right for you.
What drawbacks did parents of children with diabetes find when using a CGM?
For the parents in Dr. Tanenbaum and parents that we spoke to, the biggest drawback of using a CGM were:
- included issues with accuracy
- bleeding with CGM insertion
- occasional technical issues
- a high level of stress and worry when data were unavailable
- cost
Is it worth it?
CGM is the best way to control blood sugar. CGMs are not all the same. You have to find the one that works for you.
We have shared with you some of the benefits and drawbacks of a Continuous Glucose Monitor. Should you get a CGM though?
As with everything else in diabetes care, it is a decision that you will have to make for yourself. For some people, the value of data and peace of mind is worth every penny that they have to spend. They will fundraise and go without so that they can have access to a CGM.
In other cases, people with diabetes find that they are overwhelmed and frustrated by their Continuous Glucose Monitors. For them, these are devices best left on the shelf.
Compare the features. Look at the number of calibrations required for the CGM you are considering. Check to see how long a sensor will last and then ask to try them out. Like an insulin pump, a continuous glucose monitor is a big investment. If you don’t like the system, you won’t use it and won’t see the benefits.

Compare CGM Features
Download the free PDF to compare Continuous Glucose Monitors

One drawback is sensitivity to the adhesive. I have that. That spray (flonase?) worked for 12 days till I bumped off the libre. tape allergy or adhesive sensitivity is a drawback to any of these devices that get stuck on the body. We have a pump and a compatible cgms (Medtronic 670 G with Guardian 3 cgms). Only a little scallop-shaped transmitter and a dime sized sensor is visible on the body. That’s not much to add once you have a pump with a set in place. The pump and cgms combination especially if you have Auto Mode or Control I.Q. takes some of the load off parents and adults and caregivers of adults.