Understanding your Vitamin D (25-Hydroxy Vitamin D) results
The 25-hydroxyvitamin D test, written 25-OH-D on some reports, measures the main form of vitamin D circulating in the blood. The liver makes this form from vitamin D3, which comes from sunlight on the skin and from food. Results are reported in ng/mL or nmol/L; multiply ng/mL by 2.5 to convert to nmol/L. Vitamin D helps the body absorb calcium and supports bones and muscles.
The ranges on this page are commonly quoted adult reference ranges. Laboratories set their own, so the range printed on your report is the one that applies to your result.
Commonly quoted adult reference ranges
>>>| Parameter | Reference range | Unit | Note |
|---|---|---|---|
| Band often labelled deficient | < 20 | ng/mL | Cut-offs differ between laboratories |
| Band often labelled insufficient | 20–30 | ng/mL | |
| Band often labelled sufficient | 30–100 | ng/mL | |
| Above the usual range | > 100 | ng/mL |
What a high Vitamin D (25-Hydroxy Vitamin D) result can mean
A result above the laboratory's upper limit is uncommon and is nearly always linked to supplements, since sunlight alone does not cause it. Very high vitamin D can raise blood calcium (hypercalcaemia), which may cause nausea, vomiting, weakness and kidney stones. A doctor will usually ask about any supplements you take and may check your calcium level.
What a low Vitamin D (25-Hydroxy Vitamin D) result can mean
A result below the laboratory's lower limit is described as deficiency or insufficiency, depending on the bands the laboratory uses. Low vitamin D can be associated with tiredness, bone or muscle aches and muscle weakness, although many people with a low result have no symptoms. Long-lasting, severe deficiency causes rickets in children and is linked to bone loss in adults.
How a doctor reads the result
A doctor will usually interpret a vitamin D result alongside your symptoms, diet, sun exposure, any supplements and other results such as calcium. Pregnancy, childhood and conditions that affect absorption from the gut change how a result is read. Whether a supplement is needed, and how much, is a decision for a doctor who has seen your result.
Follow-up a doctor may arrange
If the result is low, a doctor may suggest a supplement and a repeat test to see how the level has responded. If it is high, a doctor may review the supplements you take and check blood calcium. The amount and timing are decided for each person.
Related tests
>>>Vitamin D (25-Hydroxy): preparation and listed prices
No fasting is needed. Sample type: blood. The Vitamin D test is listed at AED 89 to AED 180 across 5 labs and services: AED 89 on the DarDoc website, AED 99 on the Smart Care Polyclinic website (Dubai only), AED 100 on the Healthchecks360 website, AED 149 on the ServiceMarket website (Dubai only, home visit included) and AED 180 on the Unilabs website.
Sources: Prices on this page are the ones each lab or service publishes on its own website, read between 13 October 2026 and 7 November 2026. Zavis has published prices from 6 of the 13 labs and services it lists: of the other 7, 6 do not publish per-test prices and 1 website could not be read. The websites do not all say whether VAT or a collection fee is added to a listed price, so confirm the price with the lab before you book. How Zavis sources prices.
Listed prices for the Vitamin D test, as each site names itFrequently asked questions
What are the commonly quoted reference ranges for Vitamin D (25-Hydroxy Vitamin D)?
Commonly quoted adult reference ranges are: Band often labelled deficient: < 20 ng/mL; Band often labelled insufficient: 20–30 ng/mL; Band often labelled sufficient: 30–100 ng/mL; Above the usual range: > 100 ng/mL. Laboratories set their own ranges, so the range printed on your report is the one that applies to your result.
What can a high Vitamin D (25-Hydroxy Vitamin D) result mean?
A result above the laboratory's upper limit is uncommon and is nearly always linked to supplements, since sunlight alone does not cause it. Very high vitamin D can raise blood calcium (hypercalcaemia), which may cause nausea, vomiting, weakness and kidney stones. A doctor will usually ask about any supplements you take and may check your calcium level.
Is fasting needed for Vitamin D (25-Hydroxy Vitamin D)?
No fasting is needed. Sample type: blood.
How often are Vitamin D (25-Hydroxy Vitamin D) results rechecked?
There is no single interval that suits everyone. A doctor can advise whether and how often to test, based on your health, any treatment and your earlier results.
Medical disclaimer: The information on this page is provided for general educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Reference ranges are general guidelines. Your doctor will interpret your results in the context of your full clinical picture, symptoms, and medical history. If you have concerns about your test results, always consult a licensed healthcare professional. Do not delay seeking medical advice or disregard professional medical guidance because of information on this page.