Continuous Glucose Monitoring

CGM: See your glucose in real time. Act with confidence.

A CGM shows your glucose every few minutes—without routine fingersticks—so you can spot trends, catch highs/lows earlier, and personalize habits that keep you steady.

Real‑time trends See where glucose is headed (not just a single number).
Alerts Optional notifications for highs/lows—day and night.
Fewer fingersticks* Most modern CGMs are factory‑calibrated. (*Some systems still require calibration.)
Data that teaches Learn how meals, activity, sleep, and stress affect your numbers.

How CGM works

A tiny sensor just under the skin measures glucose in the interstitial fluid. A transmitter sends readings to your phone or receiver, updating about every 1–5 minutes. Some systems pair with pumps for automated insulin delivery.

Why people use CGM

Reduce surprises

Real‑time alerts can warn you before you crash or spike, giving you time to act—eat, dose (if applicable), or move.

Personalize routines

See your own response to foods, bedtime snacks, and morning routines (like deep breathing + water + a 10‑minute walk).

Share data (optional)

Many apps let you share readings with family or caregivers for added peace of mind.

Integrate with devices

Some CGMs connect to smartwatches and insulin pumps (closed‑loop systems) for streamlined care.

Medical disclaimer: CGM data helps decision‑making but isn’t a substitute for professional medical advice. Always work with your clinician to choose and use a device safely.

Top CGM Options (Quick Comparison)

CGM	Wear duration	Warm‑up	Calibrations	Highlights
Dexcom G7	Up to ~10 days (with short grace period)	~30 minutes	None (factory‑calibrated)	Real‑time alerts Phone & watch apps Widely integrated
FreeStyle Libre 3 / 3 Plus	Libre 3: up to ~14 days • 3 Plus: up to ~15 days	~60 minutes	None (factory‑calibrated)	Small sensor Real‑time readings App or reader
Eversense (E3 / 365)	E3: up to ~180 days • 365: up to ~365 days (implantable)	Varies (after insertion)	Requires calibration (less frequent on newer models)	Longest wear On‑body vibrating alerts Implant by HCP
Medtronic Guardian 4	Up to ~7 days	Varies by setup	May require calibration in some modes/systems	Used with MiniMed 780G Closed‑loop integration
Dexcom Stelo (OTC)	Varies (biosensor; OTC)	—	Factory‑calibrated	Over‑the‑counter For adults not using insulin

Notes: Specific indications, ages, and coverage vary. Check official sites and your clinician/insurer for eligibility and the latest details.

Which CGM is “best”?

The best CGM depends on what you value most. Use these lenses to decide:

Accuracy & Alerts

Look for systems with strong accuracy data and reliable high/low alerts if nighttime safety is a priority.

Wear Time & Comfort

Prefer fewer insertions? Longer‑wear sensors (e.g., implantable) reduce changes but require clinic visits.

Ecosystem & Integrations

If you use a pump or smartwatch, choose a CGM known to integrate well with your devices.

Cost & Coverage

Insurance, Medicare, and pharmacy pricing differ by device. Verify benefits before you buy.

Get started

Talk to your clinician about which CGM fits your goals, medications, and lifestyle.
Confirm device eligibility, app compatibility, and insurance coverage.
Set up alerts and sharing thoughtfully—start simple, then tailor.

See comparison Contact MetaboAI

Tip: Pair CGM with practical habits—e.g., a small bedtime snack for dawn phenomenon or a calm morning routine (2‑minute breathing, water, 10‑minute walk) to smooth the “feet‑on‑the‑floor” rise.

Continuous Glucose Monitoring

CGM FAQs: quick answers to help you choose and use confidently

This page complements the MetaboAI CGM comparison with practical questions people ask about accuracy, costs, alerts, apps, and everyday use. Educational only—please work with your clinician to choose and use any device.

How accurate are CGMs? What is MARD?

MARD (Mean Absolute Relative Difference) is a common accuracy metric for CGM vs. a reference. Lower is better. Modern systems typically report MARD in the ~8–10% range in studies, but individual results vary by sensor placement, warm‑up, hydration, and rapidly changing glucose (where lag matters).

Do I still need fingersticks?

Most current CGMs are factory‑calibrated and don’t require routine fingersticks, but confirm with your model. Fingersticks are recommended if symptoms don’t match readings or when required by the device (e.g., certain modes/situations).

What are warm‑up times and wear duration?

Warm‑up: typically ~30–60 minutes before first readings.
Wear time: ~7–15 days for most disposable sensors; implantables can last months.

See the comparison table on our CGM overview page for model‑specific numbers.

Which CGM is best for me?

It depends on your goals: accuracy/alerts, wear time, comfort, app and pump integrations, and costs/coverage. For non‑insulin users, new OTC options may be appropriate; for insulin users or pump users, look for proven integrations and robust alerts. Discuss with your clinician.

Will CGM work with my phone and watch?

Most systems support iOS/Android phones; many also show readings on certain smartwatches. Always check the official compatibility list for your specific phone OS version and watch model.

How do alerts work? Can I customize them?

High/low alerts can be toggled and customized (thresholds, repeat, sound/vibration). Start with simple defaults, then adjust to reduce alarm fatigue. Some systems also offer predictive alerts.

What about costs and insurance?

Pricing varies by device, pharmacy vs. DME channel, and your insurance/Medicare plan. Check benefits in advance. Ask your clinician if prior auth is needed and whether a pharmacy fill is possible (often simpler).

Are there OTC (over‑the‑counter) CGMs?

Yes—newer OTC CGMs are emerging for adults not using insulin. Availability and indications vary by country; always review the latest label and speak with a clinician if unsure.

Any tips for exercise, sleep, and daily routines?

Exercise: Expect drops with cardio and possible rises with intense anaerobic work; use trend arrows to prepare.
Sleep: Set night alerts conservatively to reduce false alarms; consider phone “focus” modes.
Morning: If you notice a “feet‑on‑the‑floor” rise, try a calm routine: 2‑minute deep breathing, a glass of water, and a 10‑minute walk.

Skin and adhesive issues—how can I improve wear?

Clean and dry the site; avoid lotions/oils before application.
Consider barrier wipes, adhesive patches, or over‑patches from the manufacturer.
Rotate sites to reduce irritation and scarring.

Travel and airport security?

Most CGMs can go through metal detectors; some advise avoiding full‑body scanners—check your device guidance. Carry backups (sensors, chargers) and a letter/card stating you wear a medical device.

Data privacy and sharing

You can usually share data with family/caregivers and sometimes with clinics automatically. Review app permissions and sharing settings; export your data if you prefer local copies.

Getting started: setup and first week tips

Apply the sensor on a recommended site and allow the full warm‑up before decisions.
Keep alerts simple at first; adjust after a few days.
Log a few meals and short walks to see your trends.
Pair with habits you like (e.g., small bedtime snack to ease dawn phenomenon).

Questions or suggestions?

We’d love to hear what’s working for you and what you want to learn next. This page is educational and not medical advice.

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