> For the complete documentation index, see [llms.txt](https://docs.tryterra.co/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.tryterra.co/faq/help-topics/data-api-sdk/provider-coverage-and-per-provider-data-availability/apple-body-composition-fields-missing.md).

# Why is Apple Health body composition data missing?

**Apple Health does not have skeletal muscle mass or visceral fat as data types**, so there is nothing to read or pass on for an Apple connection.

* **Lean body mass** is supported, but only appears when the source app writing into Apple Health records it.
* There is no separate body fat mass field. Body fat comes through as a **percentage** for every source, so absolute mass is derived from weight times that percentage.

For a full composition breakdown, a dedicated body-composition source like **InBody** is the right provider.


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