Panel guide
Vitamin D
25-hydroxyvitamin D is the usual laboratory marker for vitamin D status.
General biomarker education — not personalized medical advice. Learn more
What it measures
Most reports list 25-hydroxyvitamin D, often in ng/mL. Assay methods and ranges vary between laboratories.
Why people track it
Vitamin D is commonly included in wellness panels. Tracking confirmed values helps organize seasonal or year-over-year history.
How to read your report
Supplement timing and sun exposure can influence results. Always verify extracted numbers against your source report.
Important note
This is general information about laboratory markers. It is not a diagnosis, treatment plan, or personalized medical advice. Discuss your results with your clinician.
Upload the report you just learned to read
Confirm extracted values against your source PDF. Charts use the range printed on that report.
See how it works →Questions for your clinician
- How does this vitamin D level compare with my previous tests?
- Do you recommend any change in testing frequency?