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What is a Continuous Glucose Monitor (CGM)?

A continuous glucose monitor (CGM) is a wearable sensor that tracks your glucose levels throughout the day and night, providing real-time data on how your body responds to food, activity, stress, and sleep. Unlike traditional fingerstick tests, CGMs measure glucose in interstitial fluid every few minutes, allowing for early detection of spikes, crashes, and trends that blood tests alone might miss. This data empowers users to make informed lifestyle changes to support stable blood sugar and long-term metabolic health.

Why is glucose important?

Glucose is the primary energy source for the body’s cells and is tightly regulated to maintain optimal function. Stable glucose levels are crucial for brain function, muscle activity, hormonal balance, and metabolic health. Chronically elevated or unstable glucose levels are associated with increased risk of diabetes, cardiovascular disease, and cognitive decline.

What is Glucose Variability?

Glucose variability describes how much your glucose levels fluctuate throughout the day. High glucose variability, especially frequent or large swings between highs and lows, has been linked to increased oxidative stress, inflammation, and blood vessel damage. These effects may raise the risk of complications such as heart disease, nerve damage, and eye disease, even when average glucose appears normal.. Studies show that reducing glucose variability can independently improve outcomes, especially in people with diabetes.

CGMs provide tools like standard deviation (SD) and coefficient of variation (CV) to help quantify variability:

  • Standard deviation (SD) measures how far readings deviate from your average.
  • Coefficient of variation (CV) expresses SD as a percentage of average glucose—values under 36% are generally considered acceptable.

Lower glucose variability is a sign of metabolic stability and better resilience to lifestyle factors like stress, sleep loss, or high-carb meals.

How can I better understand my glucose variability?

Glucose variability measures how much your blood sugar levels fluctuate throughout the day. Here are the general ranges for glucose variability:

Lab Range:

  • Out of range (low): <0 %
  • In range: <33 %
  • Out of range (high): >33 %

SiPhox Ranges:

  • Optimal Range: <25 %
  • Good Range: 25-33 %

Values above this range indicate high glycemic variability, which has been linked to oxidative stress, inflammation, and increased risk of cardiovascular disease and diabetes complications. Symptoms may include energy crashes, brain fog, irritability, and cravings after meals due to rapid glucose swings.

Values below this range suggest more stable glucose levels, which is generally favorable. However, extremely low variability combined with low average glucose may indicate unrecognized hypoglycemia or overcorrection with medications.

How can I improve my glucose levels?

Use your CGM to identify patterns. Continuous glucose monitors offer powerful real-time insights. Tracking how meals, exercise, stress, and sleep affect your glucose allows you to fine-tune your habits and improve control.

Eat to minimize glucose spikes. A diet rich in fiber, lean protein, and healthy fats helps keep glucose stable. Avoid refined carbs and sugars, which tend to cause sharp elevations. Combining carbs with protein or fat can also slow glucose absorption.

Exercise regularly, especially after meals. Physical activity, especially walking or light movement after eating, enhances insulin sensitivity and reduces glucose spikes. Consistent exercise helps your muscles use glucose more efficiently, supporting long-term stability.

Improve sleep and manage stress. Poor sleep and high stress elevate cortisol, which can raise blood glucose levels. Prioritizing 7–9 hours of quality sleep and practicing stress-reducing techniques like meditation or deep breathing can improve glucose control.

Take your medications as prescribed. If you have diabetes, following your physician’s treatment plan is essential. This includes taking oral medications or insulin as directed, checking your glucose regularly, and attending follow-up visits. Medication adherence plays a critical role in preventing complications and keeping your glucose levels within a healthy range.

Where can I learn more?

DISCLAIMER: IF YOU ARE CONCERNED WITH ANY OF YOUR RESULTS, PLEASE CONSULT WITH YOUR PHYSICIAN.