β All markers
Vitamins & Minerals Β· ng/mL
Serum 25(OH)D
The definitive test for vitamin D status.
What it is
25-hydroxyvitamin D is the form of vitamin D measured in blood to assess total body stores. It is the correct test for vitamin D β not the active form (1,25-OH), which can appear normal even when stores are depleted.
Why it matters
Vitamin D deficiency is extremely common in Central Europe, especially in winter. Deficiency impairs immune function, mood, muscle strength, and is associated with worse outcomes in multiple cancer types. Tracking serum levels tells you whether your supplementation is working.
How to test
Standard blood panel, specify 25(OH)D. No fasting required.
This information is for educational purposes only. Always discuss testing and interpretation of results with your care team.
Optimal range
Below 30 ng/mL
deficient β supplement urgently
50β80 ng/mL
optimal range
Above 100 ng/mL
review supplementation dose
How often
Every 3β6 months, especially in winter.
Tags
immunity
bone
oncology
hormone