Vitamin D (25-OH)
Vitamin D (25-OH) measures the level of 25-hydroxyvitamin D in your blood, the main form used to assess your vitamin D status. Vitamin D helps your body absorb calcium and is essential for bone healt…
Category: Vitamins & Minerals
Also known as: vitamin d, vit d, 25-oh vitamin d, 25-hydroxyvitamin d, calcidiol, 25ohd, d3, vitamin d3
Reference range: 30–100 ng/mL (Source: ABIM)
Standard unit: ng/mL
High values may indicate
High vitamin D levels may indicate excessive supplementation or vitamin D toxicity, which can cause hypercalcemia, nausea, kidney damage, and abnormal heart rhythm.
Low values may indicate
Low vitamin D levels may indicate inadequate sun exposure, poor dietary intake, malabsorption disorders, liver or kidney disease, or increased risk of osteoporosis and bone fractures.
Frequently asked questions
- What is a normal Vitamin D (25-OH) level?
- A typical reference range for Vitamin D (25-OH) is 30–100 ng/mL (source: ABIM). Reference ranges vary by laboratory, age, and sex, so always compare against the range on your own lab report.
- What units is Vitamin D (25-OH) measured in?
- Vitamin D (25-OH) is most commonly reported in ng/mL. Labs in different countries may use other units — you can convert between them with BloodId's blood test unit converter.
- Where do Vitamin D (25-OH) reference ranges come from?
- BloodId uses ABIM standard reference ranges and educational information from MedlinePlus (see our methodology). Reference ranges still vary by lab, age, and sex, so always compare against your own report.
- Can I track Vitamin D (25-OH) over time?
- Yes. Upload results from any lab and BloodId charts your Vitamin D (25-OH) over time against its reference range, so you can see whether the trend is rising, falling, or stable.
Related biomarkers
Source: MedlinePlus, U.S. National Library of Medicine
Analyze your Vitamin D (25-OH) with AI
Chart your Vitamin D (25-OH) over time