In NutriCalc, Vitamin A is calculated from Retinol and Carotene (Retinol content plus one-sixth of Carotene).
If only the value for the Vitamin A is available, it may be possible to decide whether the Vitamin A is coming from retinol or carotene.
For example, with a tomato or carrot ingredient, carotene will be the source of vitamin A. Multiply vitamin A by six to get the carotene content.
Example: Vitamin A content of tomato concentrate = 292µg per 100g
So, Carotene content = 6 x 292 = 1752µg per 100g
For ingredients known to high in retinol, the Vitamin A can be taken to be the Retinol value.
Example: Vitamin A content of chicken liver = 9700µg per 100g
So, Retinol content = 9700µg per 100g