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Continuous Glucose Monitoring (CGM) has fundamentally transformed diabetes care, providing invaluable insights into blood sugar levels for patients managing the condition. Yet, its significance reaches beyond diabetic individuals alone. In this article, we offer an introduction to this technology and explore its implications and benefits for both people with diabetes and healthy individuals alike.

What is CGM?

A continuous glucose monitor (CGM) device is designed to consistently monitor and estimate glucose levels in the interstitial fluid, which approximates how blood sugar levels fluctuate throughout the day and night (1). CGMs are extremely useful in managing type I and type II diabetes. 

Metabolic health

Metabolic health is essential for overall health. Balanced blood sugar levels, efficient energy production, hormone regulation, and effective use of nutrients by cells characterize good metabolic health.

Poor metabolic health could lead to obesity, type II diabetes, cardiovascular disease, and other chronic diseases. People can be metabolically unhealthy and not know it. For example, the majority of the US population (88%) is metabolically unhealthy (2). Only 1/3 of people with average weight are metabolically healthy in the US. This means that even normal-weight individuals can still be metabolically unhealthy. You cannot tell if someone is metabolically healthy or unhealthy by looking at them.

Metabolic health and its connection to type II diabetes

Poor metabolic health can potentially lead to diabetes through a process involving insulin resistance and impaired glucose metabolism. When an individual’s metabolic health is compromised, the body becomes less responsive to insulin, a hormone responsible for regulating blood sugar levels. As a result, glucose accumulates in the bloodstream, leading to elevated blood sugar levels over time or hyperglycemia. Ultimately, this progression can culminate in the development of type 2 diabetes, a condition characterized by poor glucose control and the increased risk of developing diabetic complications. Therefore, maintaining optimal metabolic health is crucial in preventing the onset of diabetes.  

How does CGM work?

The general functioning of CGMs involves inserting a small sensor beneath the skin to continuously measure glucose levels in the interstitial fluid (1). The sensor then transmits this data to a monitoring device or a smartphone app, providing real-time information about glucose concentrations.

What does CGM measure?  

CGM is commonly said to measure blood glucose. It, however, measures glucose in the interstitial fluid that reflects blood glucose. Interstitial fluid is the fluid that surrounds and fills the spaces between cells in tissues.From there, the device estimates the blood glucose. This contrasts with finger prick tests that assess glucose levels in the capillary blood. This is especially important for diabetic patients as there is a delay of 5 to 20 minutes before the vascular and interstitial glucose levels reach equilibrium, making them occasionally less reliable, especially during swift fluctuations (3).

What does CGM do?

CGM offers a range of capabilities that provide valuable insights into glucose levels and trends (1):

  1. Provide continuous glucose measurements approximately every few minutes which results in around 288 readings daily.
  2. Track variations over days, providing real-time information.
  3. Facilitate the identification of patterns and trends.
  4. Enable prompt adjustments to medication or lifestyle choices.

Curious about how CGM can work for optimizing health? Learn more in our next article

Who uses CGM? 

CGMs are commonly used by patients with diabetes to help manage their blood sugar levels more effectively. By providing continuous data, CGMs offer insights into how food, physical activity, medications, and other factors impact glucose levels. This information allows for better decision-making in terms of insulin dosages, diet choices, and overall diabetes management.

In addition to assisting patients with diabetes, some people without diabetes use CGMs for various health-related purposes, such as improving dietary choices and understanding how different lifestyle factors affect blood glucose levels (4), (5).

Interested in finding out more about the usage of CGM to optimize health? Explore our next article

In conclusion, CGM has emerged as a vital tool in diabetes management, offering real-time insights into glucose levels and empowering patients to make informed decisions about their health. While our focus has been on diabetes patients, the potential applications of CGM extend beyond this population. At NEM, we recognize the importance of preventive care and the role that CGM can play in optimizing metabolic health for all individuals, not just those with diabetes. In our next article, we’ll focus more on the use of CGM for non-diabetics, exploring its potential benefits for overall health and longevity.    

Stay tuned for more insights on how CGM can support your journey towards optimal health.

Silviya Demerzhan, Ph.D.

Chief Scientific Officer, Nordic Executive Medicine
Medical review by: Dr. Mahir Vazda MD

  1. A Review of Available Systems. Pharm Ther. 2019 Sep;44(9):550–3. 
  2. Araújo J, Cai J, Stevens J. Prevalence of Optimal Metabolic Health in American Adults: National Health and Nutrition Examination Survey 2009–2016. Metab Syndr Relat Disord. 2019 Feb;17(1):46–52. 
  3. Janapala RN, Jayaraj JS, Fathima N, Kashif T, Usman N, Dasari A, et al. Continuous Glucose Monitoring Versus Self-monitoring of Blood Glucose in Type 2 Diabetes Mellitus: A Systematic Review with Meta-analysis. Cureus. 11(9):e5634. 
  4. Juvenile Diabetes Research Foundation Continuous Glucose Monitoring Study Group. Variation of Interstitial Glucose Measurements Assessed by Continuous Glucose Monitors in Healthy, Nondiabetic Individuals. Diabetes Care. 2010 Mar 9;33(6):1297–9. 
  5. Holzer R, Bloch W, Brinkmann C. Continuous Glucose Monitoring in Healthy Adults—Possible Applications in Health Care, Wellness, and Sports. Sensors. 2022 Jan;22(5):2030.