Vitamin D
Vitamin D helps regulate calcium balance, bone health, immune function, and several signaling pathways in the body.
About this biomarker
Vitamin D is a fat-soluble nutrient and hormone precursor involved in calcium absorption, bone maintenance, muscle function, and immune signaling. Low levels are common and may reflect limited sun exposure, low intake, absorption issues, or other health factors.
Why it matters
Vitamin D status can affect bone strength, calcium handling, muscle performance, and broader health patterns. Tracking it over time helps identify whether levels are improving, stable, or consistently low.
What lower levels may suggest
Lower levels may be associated with reduced sun exposure, low dietary intake, malabsorption, or other factors affecting vitamin D status.
What higher levels may suggest
Higher levels may occur with heavy supplementation or less commonly with other medical causes. Interpretation should always use the lab reference range and full context.
Common tests
Usually measured as 25-hydroxy vitamin D on standard bloodwork.