Both Dexcom and FreeStyle Libre write glucose data to Apple Health. Here is exactly what syncs, how to enable it, and what you can do with the data once it is there.
Dexcom G7 and Apple Health
Enable: Dexcom app → Settings → Share with Apple Health. Toggle on Blood Glucose. Data writes immediately and retroactively for the sensor session.
What syncs: glucose readings every 5 minutes, labeled as “Blood Glucose” in Health. Trend arrows do not sync — only numeric values.
FreeStyle Libre 3 and Apple Health
Enable: LibreLink → Settings → Connected Apps → Apple Health. Toggle Blood Glucose.
What syncs: glucose readings every minute (Libre 3 updates more frequently than Dexcom). Values appear in Health as “Blood Glucose.”
What You Can Do With CGM Data in Apple Health
- Share with healthcare provider: Export Health data as a PDF from the Health app for clinic visits
- Third-party apps: Carb counting apps, diet trackers, and activity apps can read your glucose to provide context
- Correlations: Health’s native trend analysis can show connections between activity, sleep, and glucose
Limitations
- Apple Health does not display trend arrows — only numeric values
- No alarms or alerts in Apple Health directly
- Data is read-only from Health into third-party apps — apps cannot write back to your CGM
Privacy
CGM glucose data in Apple Health is encrypted and stored on-device. Third-party apps accessing Health data must request permission for each data type. Review your Health → Privacy → Apps permissions regularly.