Retinol activity equivalence

Values of RDI and RDA for vitamin A are given as retinol activity equivalents (RAE) where 1 microgram of retinol equals 1 RAE, 12 micrograms of p-carotene equals 1 RAE, and so forth for all provitamins A. 

The U.S./Canadian Dietary Reference Values report (Institute of Medicine, 2001) introduced the term retinol activity equivalent to take account of the incomplete absorption and metabolism of carotenoids 1 RAE = 1 /xg of all-fra s-retinol, 12 /xg of /3-carotene, and 24 /xg of a-carotene or /3-crypto-xanthin. On this basis, 1 iu of vitamin A activity = 3.6 /xg of /3-carotene or... 

Institute of Medicine to recommend the retinol activity equivalent (RAE) as the basis of calculation of retinol intake. In this system, a ratio equivalence of 1 12 24 is recommended (i.e., 12jLlg p-carotene or 24 Ug mixed carotenoids has the same biological activity as IjLig retinol). Using this system, current RDAs for vitamin A are 900 pg RAE for men 19 years and older 700 ug RAE for women 19 years and older, with up to 770 xg RAE/day in pregnancy and up to 1300 fig RAE/day in lactation 300 to 900 fig RAE for children 1 to 18 years, dependent upon age and sex and for infants an adequate intake (AI) of 400 fig RAE at 0 to 6 months and 500 fig RAE from 7 to 12 months. ... 

Vitamin A (international unit) Vitamin A (retinol activity equivalents) Retinol... 

As retinol activity equivalents (R AEs). 1 RAE = 1 pg retinol, 12 pg p-carotene, 24 pg a-carotene, ot 24 pg p-cryptoxanthin. The RAE for dietary [wovitamin A carotenoids is twofold greater than retinol... 

Vitamin A is available either from (i) preformed retinol (present in animal foods as retinyl esters), or (ii) metabolised from provitamin A precursors. The recommended dietary allowance for preformed vitamin A is 0.9 mg/day for men and 0.7 mg/day for women. Provitamin A somces are graded according to their retinol activity equivalence (RAE), e.g. since 12mg of 3-carotene in food 5delds Img retinol, its RAE is 12. 

The Food and Nutrition Board of the Institute of Medicine revised the Recommended Dietary Allowance (RDA) of vitamin A in 2001 as 900 retinol activity equivalents (RAF) for men and 700 RAF for women. The RAF was introduced to avoid the ambiguity of international units (lU), which arises because 1 lU of vitamin A (0.3 pg) and 1 lU of the vitamin A precursor (provitamin A) all-tra s-/ -carotene (0.6 pg) do not have the same biological activity. Rather, 6 lU of /3-carotene and 12 lU... 

RAE, Retinol activity equivalents trials providing 60 mg RE gave a half dose to infants <12 months. 

Owing to the multiple forms of vitamin A in most diets and the lower efficiency of utilization of carotenoids compared to preformed vitamin A, the total amount of vitamin A (bioactivity) in foods or in the total diet must be expressed in equivalents. Over the years, several equivalency units and conversion factors have been adopted. Most recently, the retinol activity equivalent was adopted by the Institute of Medicine (lOM) in 2001 to replace older units of bioactivity because new information indicated that the conversion of carotenoids is less... 

Table 2 Recommended dietary allowances (RDA) for vitamin A in micrograms ( g), retinol activity equivalents (RAE) and international units (lU), and tolerable upper intake levels (UL, pg retinol day" ) for children and adults ...

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