Continuous Glucose Monitors for People without Diabetes?
Continuous Glucose Monitors (CGMs) are an excellent technological tool created to help people with diabetes better track their blood sugars and monitor their glucose profiles. Recently people without diabetes have begun using these CGMs for weight loss programs and lifestyle modification programs. Doctor Viral Shah conducted research into how the health metrics of CGMs translates to those without diabetes and if using a CGM is actually helpful without diabetes.
A study looking at the accuracy of HbA1c (a lab value used to diagnose and monitor diabetes) estimated by a CGM and a lab measured HbA1c in people without diabetes found that the CGM overestimated by 0.6% which can lead to a misclassification of diabetes and pre-diabetes in those that are not already diagnosed. The metrics that are measured and calculated by a CGM are specifically created for those with diabetes that have insulin resistance or an inability to produce insulin (the hormone that regulates blood sugars by initiating the storage of glucose in cells, subsequently lowering the amount of glucose circulating in the blood). A high blood sugar in someone without diabetes means something different than for someone with diabetes because the body can respond to the high blood sugar and appropriately store it. Those without diabetes should still be mindful about how often they are causing major spikes in their blood sugars because that can lead to the development of type 2 diabetes, but a high blood sugar now and then does not automatically mean the body is inappropriately responding to glucose with insulin.
An additional study found that CGMs might have lead to behavioral modifications in food selection and physical activity, but the data is very limited on if CGM use actually facilitated lasting lifestyle changes. The idea behind using a CGM for weight loss is to monitor the different spikes that occur when taking in different foods and learning what foods better maintain steady blood glucose levels. It can also prompt someone to take a walk or participate in some kind of physical activity when they see a high blood glucose level. However, as stated above, studies have not yet found that using the CGM in this way produces lasting changes to lifestyle.
The big concern with using CGMs when someone does not have diabetes is misinterpretation and misuse of the data. Without the appropriate understanding of diabetes and blood sugars people can be lead to believe they have pre-diabetes or diabetes when they truly do not. CGM data output was not created or calculated for people without diabetes so the interpretation of the data is inappropriate for them.
Metabolic health is absolutely something that every person should strive for by limiting added sugar intake, increasing fiber, being sure to eat balanced meals and snacks, and being physically active. There is benefit to someone seeing how their blood sugars are effected by certain foods since it is not something that can be felt, however until a CGM is adapted for someone without diabetes and can appropriately and accurately show their blood glucose metrics it is not the right tool for the job.
Resources:
Endocrinetoday: Volume 21, No 7, July 2023, pg 25
Written by: Meghan Hawley, RD, Ellen Byron & Associates
