Written and medically reviewed by Nicole Grant, RD
Continuous glucose monitoring is now receiving attention for its potential applications and benefits beyond the diabetic community. Unlike traditional glucose-testing methods, such as finger-prick measurements, a continuous glucose monitor (CGM) provides an ongoing stream of glucose data, offering a detailed picture of how an individual’s glucose levels fluctuate throughout the day. For people without diabetes, this real-time data can be a powerful tool for understanding how fasting, exercise, and other lifestyle practices affect blood sugar levels, which in turn affects fat loss and overall metabolic health.
What Is Continuous Glucose Monitoring?
Continuous glucose monitoring is a method for regularly tracking glucose (sugar) levels in the blood. To fully understand its importance, it is first helpful to grasp the basics of blood-sugar regulation.
In your body, glucose serves as a primary energy source, and its levels are carefully regulated by hormones like insulin and glucagon. Once consumed, carbohydrates are broken down into their component parts, i.e., glucose, which causes blood-sugar levels to rise. Insulin, produced by the pancreas, helps cells grab that glucose for energy, thereby removing it from the blood and lowering blood-sugar levels. Of course, your body doesn’t want blood sugar to get life-threateningly low, so between meals or during fasting, the hormone glucagon helps you maintain normal blood-sugar levels by prompting the liver to release stored glucose. Throughout the day, your body typically functions best when blood-sugar levels are kept around 70–140 mg/dL.
CGMs track these blood-sugar changes in real time. They typically collect a few hundred data points throughout the day and transmit the data to your phone or another device where you can check your levels in real time. The feedback is immediate, which is beneficial for showing a direct connection to your daily lifestyle choices.
How Does Continuous Glucose Monitoring Fit into Your Health Journey?
Blood-sugar management is important in non-diabetics because it can directly influence your ability to lose weight and gain health. “CGMs are useful to personalize prevention and treatment plans for not only type-1 and type-2 diabetes and prediabetes but also for any diseases or chronic conditions that are affected by blood sugar and insulin, like overweight and obesity, fatty liver, PCOS, sleep apnea, depression, anxiety, and possibly even some cancers and dementia,” said Dr. Naomi Parrella, Zero’s Chief Medical Officer.
Improved control of your blood sugar translates to better metabolic flexibility, meaning you can more easily switch between burning sugar (glucose) and fat for fuel. This allows your body to more efficiently burn fat and ideally leads to sustainable weight loss and weight maintenance over the long term. “For those who are trying to lose weight, specifically fat mass, it’s helpful to remember that when insulin spikes, fat burning turns off,” said Dr. Parrella. “So if someone is trying to lose their excess fat tissue, knowing which choices spike blood sugar — which likely spikes insulin, which results in turning off fat burning — is helpful.”
Optimal blood-sugar balance also reduces your risk of chronic disease such as diabetes, heart disease, neurodegenerative disease, and cancer, to name a few.
A CGM can be a powerful tool to help you adopt lifestyle and behavior changes that will improve your blood-sugar regulation. The key, according to Dr. Parrella, is to use real-time feedback from the CGM to make informed decisions about fasting, nutrition, exercise, and other lifestyle activities to better control your blood sugar. By continuously tracking your glucose levels, you can learn which changes are most effective to achieving weight and health goals to get better results, faster.
Intermittent fasting positively impacts glucose levels, which you can observe on a CGM. By continuously monitoring your glucose, you can study how your body responds to periods of fasting and refeeding. These data help in identifying the optimal fasting duration for your body, ensuring that you maintain glucose levels within a healthy range and avoid extreme highs or lows. It also allows you to fine-tune your eating windows, tailoring them to when your body best metabolizes foods, and thereby optimizing post-meal glucose responses — which, studies show, can be a game-changer when it comes to reducing cardiovascular disease.
Additionally, CGM data can highlight the impact of other lifestyle activities, such as physical activity, on glucose management. Seeing how your workouts influence your blood sugar can provide a boost of motivation to exercise more regularly, and getting this granular feedback can help you to determine the best workout timing and intensity for optimal glycemic control.
What Are the Benefits and Limitations of Tracking Glucose Levels?
Continuous glucose monitoring can provide a variety of benefits to your health. However, as with most things, it does come with some limitations, as well.
CGM benefits include…
- Improved metabolic awareness. Regular glucose monitoring provides valuable insights into how different factors like fasting, nutrition, exercise, stress, and sleep patterns affect blood-sugar levels. This awareness can guide healthier lifestyle choices that improve glycemic control and metabolic health.
- Diet optimization. By observing how certain foods affect glucose levels, you can tailor your diet for better glycemic control, which is particularly beneficial for fat loss and overall metabolic health.
- Preventive healthcare. For people without diabetes, monitoring glucose can help in early detection of potential metabolic issues, such as chronically elevated glucose levels, which can lead to prediabetes and metabolic syndrome.
- Enhanced athletic performance. Athletes can use glucose data to optimize their diets and training regimes for better energy management and performance.
- Personalized health insights. Continuous glucose monitoring provides personalized data that enable tailored strategies for health and wellness that are tailored to the individual, as opposed to generic health and wellness recommendations.
CGM limitations include…
- Limited data. CGMs provide only one piece of your picture of health. Blood glucose is an important marker of metabolic health, but it is only one data point of many.
- Cost and accessibility. CGMs can be expensive. They typically cost hundreds of dollars per month and are usually not covered through insurance if you do not have a diagnosis of diabetes.
- Data overload. The continuous stream of glucose data can be overwhelming. Without proper context or guidance from healthcare professionals, there’s also a risk of misinterpreting the data, which can lead to unnecessary stress or incorrect self-management decisions.
How Do You Use a CGM Device?
Using a CGM is a straightforward process that integrates seamlessly into daily life. First, you attach the CGM sensor, a small, discreet device, to the body, typically on your abdomen or arm. This sensor, which is inserted just under the skin, continuously measures glucose levels in your interstitial fluid (i.e., the fluid that surrounds your cells). Once activated, the CGM sensor starts transmitting real-time glucose data to the receiver or mobile app, displaying current glucose levels and trends.
Everyone’s journey and outcomes will be different. However, a few key markers are important for virtually everyone to track:
- Average glucose. An average of 114 mg/dL or less keeps you out of the prediabetes range, but typically the lower the average, the better.
- Standard deviation. Lower standard deviation usually means less variation in your blood sugar. This means fewer spikes and crashes and more stable blood-sugar control, which can improve energy, hunger levels, and overall mood.
- Time within range. A blood sugar level between 70–140 mg/dL has been associated with improved health outcomes. Therefore, most people would benefit from keeping blood glucose within this range as much of the time as possible. However, it is always best to consult with your doctor to understand what range is best for you.
- Patterns over time. Are your averages (average glucose, standard deviation, time within range) generally above or below the standard you’re aiming for? Identifying when these levels tend to be high or low — e.g., mornings or later evenings — can help you pinpoint the right adjustment to make at the time they can be most effective.
As someone without diabetes, the frequency and duration with which you use a CGM may vary. Typically, a few weeks up to a few months is enough time to observe patterns in how your current lifestyle habits influence your blood sugar and health and to make meaningful change. After that, you can wear your CGM to check in once or twice a year, but the key is to find a way to create consistency and accountability with your new habits beyond when you are wearing the CGM. An app like Zero may just be the tool to take your CGM insights to the next level!
How to Use a CGM with Zero
Once you understand why and how to use a CGM, you’ll want to pair that data with your lifestyle choices to understand how different activities, foods, fasts, and moods affect — and are affected by — your blood sugar. This is where Zero comes in. It’s not only an app for tracking your fasting habits, it’s also a health-habits hub where you can monitor your meals, movement, sleep, and mood, all of which influence your blood sugar. By simultaneously tracking your glucose data with your lifestyle choices, you can identify trends that positively or negatively impact your blood-sugar control. From there, you can make informed decisions on what to change in order to optimize your blood sugar (and, ultimately, your health) and use Zero to help you make those changes stick.
Conclusion: CGMs Are One Helpful Tool in the Toolbox
CGMs can be a helpful health-management tool. They can empower you to make more informed lifestyle choices by offering a more robust understanding of your body’s individual glucose regulation compared to traditional blood-sugar monitoring, and this understanding can lead to choices that improve your health and well-being. However, it’s important to recognize that CGMs are just one of many tools available for enhancing health and wellness. They work best when integrated into a broader health strategy that includes fasting, balanced nutrition, regular physical activity, stress management, and adequate sleep. Health is a multifaceted journey, and the path to optimal wellness varies from person to person. Thus, while CGMs can be a powerful instrument for many, they should be considered as part of a holistic approach to health, complementing other strategies and interventions tailored to individual health needs and goals.
- Why Should We Care About Hormones? Fasting and Hormone Health - April 1, 2024
- Should You Consider a Continuous Glucose Monitor (CGM) If You’re Non-Diabetic? - March 18, 2024
- All About Insulin and Its Effect on Your Weight-Loss Journey - February 19, 2024
