Vitamin D Binding Protein (DBP) – Serum Concentration
This test measures the level of vitamin D binding protein, a protein in your blood that helps transport vitamin D and other fat-soluble compounds.
["Understanding your vitamin D binding protein levels can help assess how well your body processes certain nutrients."]
Key facts at a glance
- LOINC
- 88135-9
- Short code
- VZV Corn/Cnjt Ql Cult
- Synonyms
- VZV Corn/Cnjt Ql Cult
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- organism-specific-culture
- 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
What Is This Test Measuring?
Vitamin D binding protein (DBP) is a globulin protein found in the blood that binds to vitamin D, calcium, and other fat-soluble hormones. While vitamin D itself is measured separately, DBP plays a role in regulating calcium metabolism and hormone transport. This test evaluates the concentration of DBP in your serum sample, which may be relevant if you have conditions affecting vitamin D or calcium balance.
Why Might You Need This Test?
Your healthcare provider may order this test if you have symptoms or risk factors related to vitamin D deficiency, kidney disease, or conditions affecting protein metabolism. It may also be part of broader evaluations for metabolic disorders or genetic conditions involving hormone transport.
What Does a Result Mean?
Results are not typically provided as standalone values for DBP alone, as reference ranges vary by lab and may not be widely standardized. Instead, this test is often used in conjunction with other measurements (e.g., vitamin D levels) to assess systemic function. Abnormal levels may suggest underlying metabolic or genetic conditions.
How Is This Test Performed?
A blood sample is drawn from a vein in your arm. The serum portion (liquid part after clotting) is separated and sent to a lab for analysis using an immunoassay or similar method to quantify DBP concentration.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
While DBP itself is not directly linked to most clinical conditions, its role in transporting fat-soluble hormones and vitamins makes it relevant in certain contexts. For example, in kidney disease, DBP levels may be affected due to altered protein synthesis. Additionally, genetic mutations affecting DBP can lead to rare disorders like hypocalcemia or vitamin D resistance. This test may be part of a broader evaluation if symptoms or lab findings point toward metabolic or endocrine issues.
Short name
Vitamin D Binding Protein (Serum)
Frequently asked questions
What does a high or low DBP level mean?
How long does it take to get results?
Can I fast before this test?
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