Unit Conversions
The contents of three ingredients (Vitamin A, D, and E) are expressed as International Units (IU) on dietary supplement and food labels. Guidelines for converting units of IU to mg are given below.
For these calculations, the formulas are:
• To convert Vitamin A as retinol:
From IU to mcg: IU * 0.3 = mcg
For example: 5000 IU * 0.3 = 1500 mcg
From mcg to IU: mcg / 0.3 = IU
• To convert Vitamin A as beta-carotene:
From IU to mcg: IU * 0.6 = mcg
For example: 5000 IU * 0.6 = 3000 mcg
From mcg to IU: mcg / 0.6 = IU
• To convert Vitamin D:
From IU to mcg: IU * 0.025 = mcg
For example: 400 IU * 0.025 = 10 mcg
From mcg to IU: mcg / 0.025 =IU
• To convert Vitamin E if the product label has DL-Alpha-tocopherol as the ingredient:
From IU to mg: IU * 0.9 = mg
For example: 30 IU * 0.9 = 27 mg
From mg to IU: mg / 0.9 = IU
• To convert Vitamin E if the product label has D-Alpha-tocopherol as the ingredient:
From IU to mg: IU * 0.67 = mg.
For example: 30 IU * 0.67 = 20.1 mg
From mg to IU: mg / 0.67 = IU
