Serum or plasma mass concentration of vitamin D (25-hydroxyvitamin D)
This test measures the amount of vitamin D in your blood, which helps your body absorb calcium and maintain bone health. Low levels may indicate deficiency, which can affect muscle function, bone strength, and overall health.
["Vitamin D levels help prevent deficiencies that can lead to health risks like osteoporosis or muscle weakness."]
Key facts at a glance
- LOINC
- 111023-8
- Short code
- MuV IgM Msmt Ser
- Synonyms
- MuV IgM Msmt Ser
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 82784
- 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 if you have symptoms of vitamin D deficiency, such as fatigue, bone pain, or frequent infections. It’s also recommended for people at higher risk, like those with limited sun exposure, certain medical conditions (e.g., malabsorption), or older adults. Some tests may be done to monitor treatment for conditions like rickets or osteoporosis.
What to Expect Before the Test
No special preparation is usually needed, but you may be asked to fast for 8–12 hours before the test if it involves drawing blood from a vein. If you’re taking vitamin D supplements, let your provider know to avoid interfering with results.
What Happens During the Test?
A healthcare professional will insert a small needle into a vein in your arm to draw blood. You may feel a slight pinch, but it’s usually over quickly. The blood sample is then sent to a lab for testing.
What Are Possible Results?
Results are typically reported as a numerical value (e.g., micrograms per deciliter or nanograms per milliliter), but your provider will interpret them based on your health and symptoms. Very low or very high levels may require further evaluation.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Vitamin D deficiency is linked to weakened bones, muscle weakness, and an increased risk of certain chronic diseases. High levels may also cause symptoms like nausea, headache, or kidney stones, though this is rare. Your provider will discuss results in the context of your overall health and any symptoms you’re experiencing.
Short name
Vitamin D Level
Frequently asked questions
What causes vitamin D deficiency?
How long does it take to get results?
Can I take vitamin D supplements if my levels are low?
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