Vitamin-D-serum Vitamin-D-serum
Vitamin D; serum Vitamin D; serum Vitamin D; serum

Vitamin D; serum

25-Hydroxyvitamin D, known for its role in bone health and calcium absorption, also appears to affect immune function, neurodegenerative and cardiovascular issues, and other conditions. Vitamin D occurs in two forms—D3 is obtained from animal diet sources and through sun exposure, and D2 is obtained through vegetable diet sources. Both forms of the vitamin are used to fortify various foods and in supplements. Doctor's Data uses the gold standard LC/MS QQQ method to measure Vitamin D2, D3 and total Vitamin D. [ LEARN MORE]

Useful for:

  • Alzheimer's Disease
  • Bone Health
  • Calcium Absorption
  • Cardiovascular Disease
  • Depression
  • Immune Function
  • Infections
  • Multiple Sclerosis
  • Neurocognitive Dysfunction
  • Preeclampsia
  • Rheumatoid Arthritis
  • Type 2 Diabetes

Turnaround Time

3 to 5 days

Note: Turnaround times on results are an estimate and are not guaranteed. The lab may need additional time due to holidays, confirmation/repeat testing, etc. You can contact us to discuss when your results should be ready.

Analytes Tested

Click any analyte name for additional clinical information, including reference ranges, specimen collection, stability and rejection criteria.


List price applies when filing with insurance or Medicare, or when billing a patient directly. Prompt payment pricing applies when billing to a physician account or prepayment is received with the test.

Doctor's Data offers profiles containing multiple analytes. *Multiple analytes may be billed under a single CPT code. Many analytes can be ordered individually. Pricing may vary. Click on a specific analyte for more information or read our detailed billing and payment policies.

The CPT codes listed on our website are for informational purposes only. This information is our interpretation of CPT coding requirements and may not necessarily be correct. You are advised to consult the CPT Coding Manual published by the American Medical Association. Doctor's Data, Inc. takes no responsibility for billing errors due to your use of any CPT information from our website.

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Detailed Information

25-Hydroxyvitamin D is the major circulating form of vitamin D. It occurs in two forms: vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol), and is the precursor of the active form (1,25-dihydroxyvitamin D).

Because of its long half-life, measurement of total 25-Hydroxyvitamin D (D2 plus D3) provides the best assessment of patient vitamin D status and includes vitamin D derived from diet, supplements and exposure to UVB light, such as sunlight. Vitamin D is best known for its role in calcium and bone metabolism, but emerging research indicates that low levels of vitamin D may be associated with increased risk of some cancers, type 2 diabetes, multiple sclerosis, cardiovascular disease, rheumatoid arthritis, depression, Alzheimer's disease, infections, preeclampsia, cesarean deliveries and neurocognitive dysfunction.

Vitamin D regulates the expression of a vast array of genes in tissues including immune cells, the vasculature, muscle and reproductive organs. Vitamin D insufficiency is common and deficiency can have adverse health effects at any stage of life.

Many testing methods do not differentiate between the two forms of vitamin D, and only total concentrations are reported. This LC/MS QQQ method is sensitive and specific for both vitamin D2 and D3, and each form is measured and reported independently.