Question: 1 mg how many iu?
Answer: We've included mass equivalents of 1 IU for selected vitamins below. This information is from the Office of Dietary Supplements and the Ultimate Pharmacy Calculations Guide. Vitamin E: 1 IU is the biological equivalent of about 0.67 mg d-alpha-tocopherol, or 0.9 mg of dl-alpha-tocopherol.