Metabolic Sleep shows how your glucose behaved during the sleep session recorded in Apple Health. The card gives last night a score from 0 to 100 and a short status. Open it to see the readings behind that result, matched to your sleep stages.
Your status can be Stable, REM Spike, Deep Low, Dawn Rise, or a count of detected patterns. It points you to the part of the report worth checking first.
What does blood sugar during sleep show?
A compatible CGM provides glucose readings with a time for each reading. Body Insights matches them to the actual start and end of your recorded sleep. The result covers the sleep session in Apple Health, not a fixed block of overnight hours.
When sleep-stage data is available, Body Insights also groups the readings into Deep, Core, REM, and Awake periods. This lets you check whether a rise or dip happened during a sleep stage or near the time you woke up.
What you see in Metabolic Sleep
Last Night
A score from 0 to 100 and a status that sums up the main overnight pattern.
What happened last night
A summary with your sleep duration and the number of glucose samples used.
Glucose by Sleep Stage
See the mean, minimum, and maximum for each stage with enough data. You also get the coefficient of variation and time below the displayed threshold.
Detected patterns and Immediate Actions
The report names any patterns it found and lists checks you can make next.
What goes into the calculation?
- A valid sleep start and end time
- Timestamped readings from a compatible CGM during that sleep window
- Sleep-stage intervals when they are available
- Checks for coverage, stability, peaks, dips, and changes in direction
The score reflects overnight glucose stability, time in range, the rise near waking, and how sharply readings changed. When enough history is available, Body Insights compares the night with your own recent baseline. Until then, it uses the app's built-in baseline.
How to read a result
If the card says Dawn Rise, start with the final part of the overnight trace. Then open the sleep-stage rows. Check whether the rise appears near an Awake period or continues through a sleep stage. Compare it with several nights that had a similar sleep schedule and meal timing.
For a Deep Low or REM Spike, open the named stage first. Review its range, variability, and time below the displayed threshold. One rise or dip can come from a short data gap, sensor delay, or pressure on the sensor, so repeated patterns are more useful than one isolated point.
What happens when data is missing?
A partial night can still show a partial trace. Missing periods stay visible as gaps. Body Insights needs enough CGM coverage inside the recorded sleep window before it can present a full-night summary.
If sleep-stage data is missing, the app can still use the available overnight readings. It cannot show a stage-by-stage comparison for that period.
How to use your Metabolic Sleep result
Start with the status on the Last Night card. Open the report and find the stage or time period behind it. Then compare several similar nights before you change a routine. If you test a change, such as an earlier meal or a different workout time, change one thing and watch for the same pattern across later nights.
See metabolic sleep analysis in your own data
Body Insights shows the inputs and the change behind the result, so you can choose your next step.
See my metabolic sleep analysis