How can I convert from international units (IU) to milligrams or micrograms?
1 Answer
It varies from one substance from another.
The international unit is based on the activity or effect of biologically active substances. Here are some examples.
-
Vitamin A: 1 IU is the biological equivalent of 0.3 μg of retinol or
of 0.6 μg of beta-carotene. -
Vitamin C: 1 IU corresponds to 50 μg of L-ascorbic acid
-
Vitamin D: 1 IU is the biological equivalent of 0.025 μg of
cholecalciferol. -
Vitamin E: 1 IU is the biological equivalent of ²/₃ mg of
d-alpha-tocopherol or 0.9 mg of dl-alpha-tocopheryl acetate. -
Insulin: 1 IU is equivalent to 0.0347 mg of human insulin.
For other substances, you may have to consult a pharmacist.
EXAMPLE
The recommended dietary allowance (RDA) of Vitamin D is 600 IU. What mass of Vitamin D does this represent?
Solution
Mass of Vitamin D = 600 IU ×
