Serum or plasma probe for substance concentration of vitamin D (25-hydroxyvitamin D)
This test measures your levels of vitamin D, an important nutrient that helps your body absorb calcium and maintain strong bones. Low levels may indicate deficiency, which can affect bone health and other bodily functions.
["Vitamin D levels help assess bone health and overall nutrient status."]
Key facts at a glance
- LOINC
- 47003-9
- Short code
- VZV DNA # SerPl NAA+probe
- Synonyms
- VZV DNA # SerPl NAA+probe
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- probe-amp-tar
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why Is This Test Done?
Your healthcare provider may order this test to check for vitamin D deficiency, especially if you have symptoms like muscle weakness, frequent bone pain, or a history of osteoporosis. It’s also used to monitor vitamin D levels in people on supplements or those with conditions that affect vitamin D metabolism.
What to Expect Before the Test
No special preparation is needed. You’ll provide a blood sample, usually drawn from your arm. If you’re taking vitamin D supplements, let your provider know, as this may affect results.
What the Results Mean
Results help determine if you have sufficient vitamin D for your body’s needs. Deficiency may require dietary changes, supplements, or medical advice to address.
Common Reasons for Testing
This test is commonly performed if you have symptoms of vitamin D deficiency, have limited sun exposure, are at risk for osteoporosis, or have conditions like kidney disease that affect vitamin D processing.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Chronic low vitamin D levels can weaken bones, increase fracture risk, and may contribute to conditions like rickets in children or osteomalacia in adults. It may also play a role in immune function and other metabolic processes, though research is ongoing.
Short name
25-Hydroxyvitamin D (25(OH)D) Level
Frequently asked questions
What causes vitamin D deficiency?
How long does it take to get results?
Can vitamin D levels be affected by diet or supplements?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy