Dexcom G7 vs Freestyle Libre CGMs – A Comprehensive Comparison

Continuous glucose monitors (CGMs) are transforming how people monitor and manage their health. Whether you’re tracking glucose for energy optimization, exploring metabolic health, or managing a chronic condition, CGMs are a game-changer.

Recently, I took my glucose tracking to the next level by switching from the Freestyle Libre to the Dexcom G7 as part of my Levels Membership. Today, I’ll share my detailed comparison of these two devices, including pros, cons, and real-life examples of how CGMs can shape daily choices for optimal health. If you’ve considered trying a CGM or switching between these devices, this blog post will give you clarity.

---

Listen on Apple and Spotify!

---

What is a CGM, and Why Does It Matter?

Before we compare the Dexcom G7 and Freestyle Libre, let’s cover the basics.

A Continuous Glucose Monitor is a wearable device that tracks glucose levels in your interstitial fluid continuously throughout the day (and night). Unlike the traditional finger-prick glucometer, CGMs provide dynamic data showing how your glucose trends over time instead of a single point reading. For context:

• Glucose levels reflect how your body processes carbs, fats, and proteins, giving insights into how your lifestyle and meals affect your energy.
• CGMs are great tools for trends but may occasionally differ from finger-prick readings since they measure interstitial fluid rather than blood glucose directly.

Essentially, CGMs act like GPS for your metabolic health, guiding your choices for more balanced energy and well-being.

Comparing the Freestyle Libre and Dexcom G7

Now, onto the head-to-head breakdown of the Freestyle Libre and Dexcom G7. Both are powerful tools, but they have distinct differences worth considering, depending on your lifestyle, goals, and preferences.

Freestyle Libre Overview

The Freestyle Libre is an accessible option for those looking to get started with CGMs. Here’s what stood out to me:

How It Works:

• You need to manually scan the sensor with your phone at least once every 8 hours to capture your glucose data.
• The scanning process creates a bit more effort—you won’t see live readings unless you actively scan.

Battery Life and Setup:

• Each sensor lasts 14 days, but it takes up to 24 hours to fully calibrate after initial application. During this “warm-up” period, readings were sometimes inconsistent.
• The applicator requires you to line up the sensor and push it onto your arm. While functional, I found it slightly awkward the first few times.

Usability and Accuracy:

• The Freestyle Libre app is simple and functional, focusing mainly on glucose trends. However, its design seems more targeted toward those managing diabetes.
• The downside? I found that Libre readings were often 20+ mg/dL off compared to my glucometer, making it less reliable for pinpoint accuracy. It was helpful for spotting trends but not for exact readings.

Dexcom G7 Overview

The Dexcom G7 is a sleeker, newer CGM system with added convenience and advanced features. It elevated my tracking experience in many ways!

How It Works:

• Automatic updates via Bluetooth mean no need to scan. The readings are sent to your phone in real-time, offering a more seamless, hands-free experience.
• Each sensor lasts 10 days, with a short grace period allowing for a little more wear time.

Setup and Sensor Design:

• The Dexcom G7 features pre-assembled applicators. Just press, push, and it’s done! I barely felt the insertion. However, pressing too hard on my first try led to errors—so be gentle.

Usability and Accuracy:

• The app is robust with customizable alerts (like critical low glucose warnings), which took some getting used to. Pro tip: Adjust unnecessary notifications to avoid middle-of-the-night wake-ups.
• The Dexcom G7 readings are more in line with my glucometer, making it more reliable than the Freestyle Libre overall.

Shared Features of Both CGMs:

• Water Resistance: Both devices can handle showers, sweat, and light swimming without issues. Dexcom recommends waiting at least 12 hours after application to avoid compromising the adhesive.
• Adhesive Durability: I use performance covers included with my Levels Membership to protect the sensors during workouts or sleep. For the Freestyle Libre, replacing the cover every two weeks worked well, while the 10-day Dexcom G7 didn’t require replacements.

Real-Life Examples of CGMs in Action

The real magic of CGMs? They show how your choices affect your body in real-time. Here are some personal examples where my CGM guided me to better habits:

Post-snack check:

Eating a Perfect Bar caused a 30 mg/dL glucose rise measured with both my CGM and glucometer. This change is considered ideal and within the normal range.

Fasting Glucose Comparison from the Dexcom G7 CGM

Key Considerations When Choosing Your CGM

When deciding between the Freestyle Libre and Dexcom G7, ask yourself these questions:

• Do you value convenience? Dexcom G7 offers real-time updates without needing to scan, making it more hands-off.
• Is pinpoint accuracy a priority? For me, the Dexcom G7 provided more reliable readings closer to my glucometer, while the Freestyle Libre often had wider discrepancies.
• What’s your budget? Both devices provide valuable insights, but the Dexcom G7 tends to come at a slightly higher price point.

Ultimately, your choice depends on your lifestyle and preferences. Both devices are incredible tools to understand your glucose trends and take control of your health.

Final Thoughts on My CGM Journey

After using both the Freestyle Libre and Dexcom G7, it’s clear that each has its strengths. Personally, I find the Dexcom G7’s convenience, ease of use, and improved accuracy worth the upgrade.

That said, no CGM is perfect, and I always rely on my glucometer for confirmation when precision is a must.

If you’re considering a CGM, don’t overthink it—choose the device that aligns with your goals, and remember to focus on trends rather than fixating on individual numbers. These tools are powerful allies in optimizing your health, fine-tuning your meals, and identifying patterns that make lasting changes easier.