This post was written by Alexandra DeLellis, NP, Parkview Endocrinology.
Continuous glucose monitors (CGMs) have become a helpful tool for people with diabetes to manage their condition throughout the day. For many, they eliminate the need for multiple finger pricks; for others, they take the guesswork out of insulin dosing. However, CGM usage is gaining popularity among those living with non-insulin-dependent type 2 diabetes, people with glucose-sensitive conditions, as well as fitness and biohacking enthusiasts. In this post, we explore what CGMs can offer patients who want to understand how glucose affects their well-being.
In patients with type 2 diabetes who are not using insulin, what does the current evidence show about continuous glucose monitoring improving A1C, time in range or other clinically meaningful outcomes?
Current evidence shows that CGM use, even in patients who are not using insulin, can lead to modest reductions in A1C. Consistent CGM use often supports lifestyle change by increasing patients’ awareness of how their behaviors affect glucose levels. This awareness can help reinforce healthier habits over time and may ultimately lead to improved long-term outcomes and, in some cases, a reduced need for medication.
Do you see CGM in non–insulin-treated patients primarily as a glycemic management tool, a behavioral engagement tool or both?
I believe CGMs function frequently as a behavioral support tool, helping patients visualize the impact of food choices, physical activity, stress and sleep on their glucose levels.
From a clinician’s perspective, CGM data also provide valuable insight into glucose patterns, allowing more precise medication adjustments than intermittent fingerstick testing often allows. CGM data can also complement or clarify glycemic control when A1C may be unreliable, such as in patients with anemia.
While highly motivated patients may benefit most from using CGM, these wearables can also be particularly impactful for individuals who report "feeling fine" despite experiencing elevated glucose levels. Seeing their glucose patterns in real time can encourage noteworthy lifestyle changes.
Are improvements seen with short-term CGM use sustained after the device is removed?
In some cases, short-term or intermittent CGM use can lead to lasting behavioral improvements if patients remain engaged and apply what they have learned about their glucose responses. However, in some cases, the benefits diminish once the device is discontinued. For some individuals, when visual feedback is removed, previous habits and patterns can gradually return, worsening glycemic control.
What risks or downsides should clinicians consider when expanding CGM to this population?
Although CGM is mostly beneficial, it can have downsides. For some patients, continuous glucose visibility may increase anxiety. We may also see alarm fatigue, sleep disruption from compression lows (false readings) or overtreatment of suspected hypoglycemia (low blood sugar) when readings are not confirmed with symptoms or fingerstick testing. In other instances, patients may respond to inaccurate readings by adjusting or discontinuing medications inappropriately.
While these situations are relatively uncommon and the overall benefits of CGM generally outweigh the risks, appropriate patient education is essential. Patients should understand how to recognize false readings, when to confirm results with a fingerstick, and when to consult their provider before changing medication.
Final thoughts
CGMs have the potential to be used more widely to help support behavioral change and more informed medication management. However, successful use requires appropriate patient selection and education.
It's essential for patients to understand how to interpret CGM data, recognize common issues such as sensor errors or expected differences between CGM and fingerstick readings and use the information constructively to guide lifestyle decisions.
In individuals with very stable, well-controlled glucose levels, CGM may be less beneficial and may sometimes lead to unnecessary concern about minor fluctuations or occasional false low readings. Regardless of insulin use, education and expectations should be carefully reviewed when initiating CGM therapy.
