Functional Properties of Carotenoids in Human Health

Figures & data

Table 1 The retinol equivalency for β-carotene and other provitamin A carotenoids differ much and were recently summarized in Higdon.[82]

Retinol Activity Equivalency (RAE) for β-carotene and other provitamin A carotenoids
Quantity consumed	Retinol equivalency	RAE ratio
1 mcg of dietary or supplemental vitamin A	1 mcg of retinol∗	1:1
2 mcg of supplemental beta-carotene	1 mcg of retinol	2:1
12 mcg of dietary beta-carotene	1 mcg of retinol	12:1
24 mcg of dietary alpha-carotene	1 mcg of retinol	24:1
24 mcg of dietary beta-cryptoxanthin	1 mcg of retinol	24:1
∗One International Unit (IU) is equivalent to 0.3 mcg of retinol, and one mcg of retinol is equivalent to 3.33 IU of retinal (Adapted from Higdon[82]).

Higdon, J. Vitamin A. Linus Pauling Institute Micronutrient Information Centre. 2003. http://lpi.oregonstate.edu/infocenter/vitaminA/ (Accessed: 19 May 2005 ).

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