Vitamin D (measured as 25-hydroxy vitamin D) helps your body absorb calcium and keeps bones, muscles and the immune system healthy. Your skin makes it from sunlight.
- Normal range (adults)
- 30–100 ng/mL (75–250 nmol/L)
- Sample
- Blood
- Fasting
- Not usually needed
- Also called
- Vit D, 25-OH Vitamin D, 25 Hydroxyvitamin D, 25-OHD, VitD
Vitamin D normal range
| Group | ng/mLConventional units: US, South Asia | nmol/LSI units: UK, Europe, Australia, international |
|---|---|---|
| Adults | 30–100 | 75–250 |
Below 20 ng/mL (50 nmol/L) is deficient; 20–29 ng/mL is insufficient.
Your report may use either unit system; labs in the Gulf often print both. Ranges also vary slightly between laboratories, so the range printed on your own report is the one to go by.
Why is the Vitamin D test done?
Deficiency is extremely common, especially in the Gulf and South Asia where people avoid the sun or cover most of their skin. It is checked for bone pain, tiredness, muscle weakness, low calcium and osteoporosis.
What does a high Vitamin D level mean?
Very high vitamin D (above about 100 to 150 ng/mL) almost always comes from taking too many supplements. It can raise calcium and cause nausea, thirst, confusion and kidney stones.
Common causes
- High-dose supplements or injections taken without monitoring
- Rare conditions such as sarcoidosis
Diet and lifestyle tips
- Stop vitamin D supplements until your doctor reviews you
- Drink plenty of water
- Have your calcium checked
What does a low Vitamin D level mean?
Below 20 ng/mL (50 nmol/L) is deficient and 20 to 29 ng/mL is insufficient. Low vitamin D can cause tiredness, aches, muscle weakness, low mood and weaker bones over time.
Common causes
- Little sun exposure or covered clothing
- Darker skin, which needs more sun to make vitamin D
- Overweight
- Gut conditions affecting absorption
- Kidney or liver disease
- Older age
Diet and lifestyle tips
- Get 15 to 30 minutes of sun on arms and legs a few times a week, outside the hottest midday hours in summer
- Eat oily fish (salmon, sardines, mackerel), egg yolks and fortified milk or cereals
- Most people with deficiency need a supplement; ask your doctor for the right dose and retest after about 3 months
When should you see a doctor?
Ask your doctor about treatment if your level is below 20 ng/mL (50 nmol/L), and before taking high-dose supplements.
Last updated
This page is for general education and is not a diagnosis. Normal ranges differ between laboratories, so always compare your result with the reference range printed on your own report, and discuss abnormal results with your doctor.