Vitamin D, 25-Hydroxy, Total, Immunoassay

Select a health panel test to have a comprehensive examination of health and to save money

Vitamin D, 25-Hydroxy, Total, Immunoassay


Test Description

The Vitamin D test, also called Vitamin D 1,25 Dihydroxy Blood Test, is done to investigate a problem related to bone metabolism or parathyroid function. It is often caused by Vitamin D deficiency or malabsorption. Vitamin D 25-Dihydroxy test measure whether there is an active form of Vitamin D is produced in the liver and kidneys or not. This test is not a part of a typical routine checkup as most of the results show normal results even if there is an overall deficiency in the body. The Vitamin D 25-Hydroxy Blood Test is recommended to test the bioactive form of Vitamin D.

Importance of Vitamin D Test:
This test gives the differential diagnosis of hypocalcemia. And it helps the doctors to monitor the patients with renal osteodystrophy or chronic renal failure. The test is ordered if an abnormality is associated with the enzyme that is responsible for converting the enzyme that converts 25-hydroxyvitamin D to 1,25 dihydroxy vitamin D, or there is a chance of kidney disease. Low levels of vitamin D are the signs of early kidney failure. The test helps in aiding in the diagnosis of Parathyroid disorder or kidney failure. Furthermore, the test can be done to detect

  • hyperthyroidism
  • hypoparathyroidism
  • pseudohypoparathyroidism
  • vitamin D-resistant rickets
  • renal osteodystrophy

  • Reasons for the Vitamin D test:
    Your doctor may request you to get tested for a 25-hydroxy vitamin D test for various reasons. It can help to determine if there is too much or too little amount of vitamin D in your body that is causing bone weakness or other abnormalities. The test also monitors the risk of vitamin D deficiency.
    People who are at high risk of having lower vitamin D levels are:
  • People who don't get enough sun exposure
  • Older men and women
  • Obese people
  • Babies who are breastfed only
  • People with gastric bypass surgery
  • People who have diseases that affect their intestines resulting in malabsorption of nutrients such as Crohn's disease.

  • How is the test performed?
    The doctor will tell you not to avoid eating for 4-8 hours. Then the blood sample will be drawn, and it will be tested.
    The office of Dietary Supplements (ODS) has defined the levels of vitamin D y 25-hydroxy level. It is measured in nanomoles/liter (nmol/L) or nanograms/milliliter (ng/mL). The deficiency will have results lower than 12 ng/mL or 30 nmol/L. The ideal level is from 50 nmol/L to 125 nmol/L.
    If the levels are low, it means that:
  • You do not have a balanced diet
  • Your intestines don't absorb the vitamin properly
  • You don't spend enough time under the sun which is the main source of vitamin D

  • The high levels of vitamin D in the body are a result of taking too many vitamin pills or nutritional supplements. Even the higher levels of the vitamin can result in hypervitaminosis D, which is rare. Still, you could end up with liver or kidney problems. Consult your doctor to know more about the test and results predictions.

    Testing Info

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

    Test Instructions : Fasting preferred, but not required Please do not exercise prior to testing. It is best that your blood is taken in a rested state.

    Fasting: Yes

    Methodology: Immunoassay (IA)

    Results In: 2 Working 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 and we will contact the lab on your behalf immediately.