Vitamin D Level
Type
Blood Testing
Biomarkers
1
Duration
15 min
Results
3 days
25-hydroxyvitamin D measurement to assess vitamin D status.
A vitamin D test measures the level of 25-hydroxyvitamin D in your blood — the most accurate indicator of your body's vitamin D status. Vitamin D is essential for calcium absorption, bone health, immune function, and mood regulation. Despite its importance, vitamin D deficiency is one of the most common nutritional deficiencies worldwide, affecting an estimated 1 billion people. Low levels are linked to increased risk of osteoporosis, fractures, autoimmune diseases, depression, and certain cancers. People living at higher latitudes, those with darker skin, office workers with limited sun exposure, and the elderly are particularly at risk.
Key Details
- Biomarkers
- 1 marker (25-OH vitamin D)
- Fasting Required
- No
- Sample Type
- Blood draw
- Turnaround
- 24–72 hours
- Optimal Range
- 40–60 ng/mL (100–150 nmol/L)
- Common Use
- Deficiency screening, supplementation monitoring
Who Is This For?
Anyone living in regions with limited sunlight or who spends most time indoors. People experiencing bone pain, muscle weakness, or frequent illness. Those with darker skin (melanin reduces vitamin D synthesis). Older adults, as the skin's ability to produce vitamin D decreases with age. Anyone supplementing with vitamin D who wants to verify they're in the optimal range.
What's Included
Preparation Required
No fasting required. No special preparation needed. If you supplement with vitamin D, continue your normal dosage — the test is measuring your steady-state level, not an acute response.
- Category
- Diagnostic
- Sample Type
- Blood draw
- Duration
- 15 min
- Results
- 3 days