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Vitamin D Conversion Formula:
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Vitamin D levels can be measured in different units worldwide. The most common units are nmol/L (nanomoles per liter) and ng/mL (nanograms per milliliter). This calculator converts between these two measurement systems.
The calculator uses the conversion formula:
Where:
Explanation: The conversion factor of 2.5 is used because the molecular weight of vitamin D (cholecalciferol) is approximately 384.6 g/mol, and 1 ng/mL equals 2.5 nmol/L.
Details: Accurate vitamin D measurement is crucial for assessing nutritional status, diagnosing deficiency, and monitoring treatment effectiveness. Different regions use different measurement units, making conversion necessary for international comparison and clinical decision-making.
Tips: Enter vitamin D level in nmol/L. The value must be a positive number. The calculator will automatically convert it to ng/mL using the standard conversion factor.
Q1: Why are there different units for vitamin D measurement?
A: Different countries and laboratories use different measurement systems. nmol/L is common in most countries, while ng/mL is frequently used in the United States.
Q2: What are normal vitamin D levels?
A: Generally, levels below 50 nmol/L (20 ng/mL) indicate deficiency, 50-75 nmol/L (20-30 ng/mL) indicate insufficiency, and above 75 nmol/L (30 ng/mL) are considered sufficient.
Q3: Is the conversion factor always 2.5?
A: Yes, the conversion factor of 2.5 is standardized for 25-hydroxyvitamin D, which is the most commonly measured form of vitamin D in blood tests.
Q4: Can I convert ng/mL to nmol/L?
A: Yes, to convert ng/mL to nmol/L, multiply by 2.5 (nmol/L = ng/mL × 2.5).
Q5: Are there any exceptions to this conversion?
A: This conversion is specific to 25-hydroxyvitamin D. Other forms of vitamin D may have different conversion factors, but 25-hydroxyvitamin D is the standard clinical measurement.