Apple Health + CalorieScan AI: the right setup

Apple Health is the spine of the iOS health ecosystem and CalorieScan AI reads from it and writes to it. Done right, you get a unified picture of weight, training, and food without double-entry. Done wrong, you get duplicates, sync conflicts, and a panel of toggles you stopped trusting in week three.

What to write to Apple Health (from CalorieScan)

Turn ON in Settings → Apple Health → Allow Writing:

• Dietary Energy. Calories you logged in the app. Surfaces in Health → Nutrition.
• Protein. The macro you most want a long-term trend on.
• Carbohydrates. Useful for endurance and diabetes contexts.
• Fat. Less day-to-day useful but completes the picture.
• Fiber. If you care about gut health, surface it.

Turn OFF:

• Caffeine. We don't measure it well from photos. Use the Coffee app or a dedicated input if you care.
• Water. Same; if you're tracking water, use a dedicated app or the Health app directly.

What to read from Apple Health (into CalorieScan)

Turn ON in Settings → Apple Health → Allow Reading:

• Active Energy / Resting Energy. This is how the app calibrates your TDEE without you having to guess. If you wear an Apple Watch or carry your iPhone with you, this is meaningful data.
• Body Mass. Lets the app trend your weight over time and adjust calorie targets.
• Steps. Used for NEAT estimation when you don't have an Apple Watch.
• Workouts. So a strenuous workout day shows up as a calorie target adjustment, not a mystery.

What to leave OFF (or turn off)

• Sleep, mindfulness, heart rate variability. We don't use these. Turning them off reduces permission-prompt fatigue and protects your privacy.

The "duplicate calories burned" problem

You wear an Apple Watch. Your watch logs your run. Strava also logs your run. Both write to Apple Health. CalorieScan sees both and double-counts.

The fix: in Strava, turn off "write to Apple Health" if your Watch already logs the workout. In Garmin and similar, the same logic applies. Pick one source of truth per workout.

The weight sync ambiguity

If you weigh yourself daily on a Withings/Fitbit/Renpho scale that syncs to Apple Health, CalorieScan reads it and uses the rolling 7-day average for trend tracking. Don't enter weight manually in the app on top of that — you'll get duplicates.

What you don't have to do

• You don't need to manually enter every food again in Apple Health. CalorieScan writes it for you.
• You don't need to enter workouts in CalorieScan. Apple Health is the source.
• You don't need to use the Apple Health "track your calories" widget. Our app's widget is more legible.

What this gets you

• Weekly summaries that include your real caloric expenditure (vs. estimated).
• A weight trend that adjusts your calorie target without you re-doing the math.
• A long-term backup of your nutrition data outside our app, in your own device's health record.

A sanity check

Open Apple Health → Nutrition → Dietary Energy. You should see the same daily total CalorieScan shows. If they diverge, the most common cause is a stale food entry from another app you forgot was syncing. Audit your "Data Sources" list quarterly.

Two apps, one source of truth. Set it up once and stop thinking about it.