Vitamin D, 25-Hydroxy - NBI
Vitamin D, 25-Hydroxy - NBI

Vitamin D, 25-Hydroxy

Regular price $58.00

Vitamin D is critical for maintaining healthy levels of calcium and phosphorus by aiding in their absorption from the gut. This helps the body form and maintain strong bones. Vitamin D also modulates neuromuscular, immune, and other cellular functions. Vitamin D deficiency, as defined by the Endocrine Society, is common. As much as 68% to 77% of the population is estimated to have suboptimal (<30 ng/mL) levels of vitamin D.

Alternate names: 25 OH Vitamin D,Vitamin D, 25-OH,25-Hydroxy Vitamin D,Vitamin D, 25-Hydroxy

What’s Reported
  • Vitamin D, 25-Hydroxy, Total

Methodology: Immunoassay (IA)

How to prepare

Fasting: Fasting is preferred, but not required.

Water: Drink plenty of water to stay well hydrated.

Medications: Take all medications as prescribed.

Dietary supplements: If you take a dietary supplement containing Vitamin D, discontinue the dietary supplement 48 hours (two days) prior to the blood test. This will give a more realistic picture of a person’s Vitamin D status.

How long until you get the results

3-4 business days
Result turnaround times are estimates and not guaranteed. Due to factors outside of our control, such as weather, holidays, confirmation/repeat testing or equipment maintenance, our lab may require additional time to complete tests.

More about this test

Measurement of serum 25-OH vitamin D concentrations provide a good index of circulating vitamin D activity in patients not suffering from renal (kidney) disease. Lower than normal 25-OH vitamin D levels can result from a dietary deficiency, poor absorption of the vitamin or impaired metabolism of the sterol in the liver.

Conditions associated with Vitamin D deficiency include:

  • Back pain
  • Breast Cancer
  • Colon Cancer
  • Congestive heart failure
  • Depression
  • Heart attacks
  • Hypertension
  • Insulin resistance
  • Menopausal symptoms: vaginal atrophy
  • Menstrual Migraines
  • Multiple Sclerosis
  • Musculoskeletal pain
  • Osteomalacia and Rickets
  • Osteoporosis
  • Ovarian Cancer
  • Pancreatic Cancer
  • Polycystic Ovary Syndrome (PCOS)
  • Prostate Cancer
  • Rheumatoid arthritis
  • Seasonal Affective Disorder (SAD)
  • Type I Diabetes (Insulin Dependent)
  • Type II Diabetes (Non-Insulin Dependent)

The Endocrine Society recommends regular screening for individuals at risk for deficiency. These include people who have:

  • Osteoporosis
  • Osteomalacia and rickets
  • Chronic kidney disease
  • Diseases that require certain medications (anti-seizure medications, glucocorticoids, AIDS medications, antifungals, cholestyramine)
  • Malabsorption syndromes, including inflammatory bowel disease, Crohn’s disease, cystic fibrosis, history of bariatric surgery
  • Hyperparathyroidism
  • Hepatic failure

Screening is also recommended for:

  • African American and Hispanic children and adults
  • Pregnant and lactating women
  • Older adults with a history of falls
  • Older adults with history of nontraumatic fractures
  • Obese children
  • Obese adults

Above normal levels of vitamin D can lead to elevated calcium in the blood, called hypercalcemia.

Additional resources

The Silent Disease of Vitamin D Deficiency, by Dr. John Neustadt

Vitamin D (Mayo Clinic)


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