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Conversion Formula:
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International Units (IU) and milligrams (mg) are different measurement systems used for vitamins and medications. IU measures biological activity while mg measures mass. Conversion between them requires substance-specific conversion factors.
The calculator uses the simple formula:
Where:
Explanation: The conversion factor represents how many International Units are in one milligram of the specific substance.
Details: Proper conversion is crucial for correct dosing of vitamins and medications, as different substances have different biological activities per milligram.
Tips: Enter the amount in International Units and the specific conversion factor for the substance you're working with. Common conversion factors include Vitamin D (40 IU/mcg), Vitamin E (0.67 mg/IU for d-alpha-tocopherol), etc.
Q1: Why can't we directly convert IU to mg without a conversion factor?
A: Because different substances have different biological activities per milligram, so each substance has its own unique conversion factor.
Q2: Where can I find IU/mg conversion factors?
A: Check medication/vitamin packaging, pharmaceutical references, or reliable medical websites. They vary by substance and sometimes by form (e.g., different Vitamin E forms have different factors).
Q3: Are IU and mg interchangeable?
A: No, they measure different things (biological activity vs mass). Conversion is only meaningful when you know the specific substance and its conversion factor.
Q4: Why do some substances use IU instead of mg?
A: IU is used when the biological effect is more important than the mass, especially for substances where different forms have different potencies.
Q5: Is this calculator suitable for all substances measured in IU?
A: Yes, as long as you have the correct IU/mg conversion factor for your specific substance.