This converter will show you the conversion from IU to mcg or vice versa
Vitamin Converter
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Why do vitamins have different values?
The values for converting IU to mcg (or vice versa) are different for each vitamin because the conversion factors depend on the molecular weight and potency of the vitamin.
For example, the conversion factor for Vitamin D is 0.025 mcg per IU, while the conversion factor for Vitamin A varies depending on whether it’s being converted from IU to mcg retinol or mcg beta-carotene. This is because Vitamin D has a lower molecular weight and higher potency than Vitamin A.
Similarly, the conversion factor for Vitamin E is 0.67 mg per IU because it has a higher molecular weight and lower potency compared to Vitamin D.
Overall, the conversion factors are based on the specific characteristics of each vitamin and are determined by scientific studies and regulatory agencies to ensure accurate dosing and safety.

Thomas Sandberg CSAN, CCNC, AADP
Thomas Sandberg is a board certified animal naturopath and carnivore nutritionist. He founder of Long Living Pets Research Projects, a 30-year observational study into raw-fed dogs and cats. Thomas also consults in animal naturopathy, including the prevention of chronic diseases and longevity using all-natural modalities. With more than 20 years of experience with hundreds of cancer cases, he has a deep understanding of why so many dogs and cats get cancer today and how we can lower the risk significantly.
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