Quest Diagnostics Vitamin D Test
Type
Blood Testing
Biomarkers
1
Duration
30 min
Results
3 days
Vitamin D blood test measuring 25-hydroxyvitamin D levels, essential for bone health.
This test measures the amount of 25-hydroxyvitamin D in your blood. Your body absorbs vitamin D when exposed to sunlight or consuming fortified foods – storing it in fat cells until needed for use. Your liver and kidneys convert this inactive vitamin D to 25-hydroxyvitamin D, the active form the body needs. Vitamin D deficiency can indicate bone disease, nutrition disorders, or other metabolic complications. Buy your own vitamin D lab test online with Quest. No doctor’s visit is required – simply purchase vitamin D testing, visit a nearby Quest® location for sample collection, and get fast results.
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.
Biomarkers Tested
1The best indicator of overall vitamin D status. Vitamin D is essential for calcium absorption, bone health, immune function, and mood regulation. Deficiency is extremely common, especially in northern latitudes, and linked to increased disease risk.
+ $6.00 Physician Service Fee
- Category
- Diagnostic
- Sample Type
- Blood draw
- Duration
- 30 min
- Results
- 3 days