Question: what is the difference between vitamin a rae and vitamin a iu?
Answer: An RAE can't be directly converted into an IU if you don't know the source of vitamin A. Conversion rates between mcg RAE and IU are: 1 IU retinol = 0.3 mcg RAE. 1 IU beta-carotene from dietary supplements = 0.15 mcg RAE.