Betacarotene (Provitamin A)
Vitamin A occurs in nature in two forms, as Retinol andBetacarotene. Retinol is preformed vitamin A and is only found
in foods of animal origin eg. fish oils, liver etc. Retinol is
produced by the animals from betacarotene. Retinol and its
ether, aldehyde and acid derivatives have vitamin A activity.
Vitamin A is fat soluble and so requires fats as well as
minerals to be properly absorbed by the body.
Plants can synthesis carotenoids, which are the precursors of
vitamin A. Betacarotene has vitamin A activity, and is the most
plentiful and has the mst biological activity. Betacarotene is
found in green vegetables and carrots. Our bodies can convert
betacarotene into vitamin A as required. Any betacarotene not
converted circulates in the blood acting as a powerful
antioxidant and quencher of singlet oxygen - a non-radical form
of activated oxygen that can damage cells. Over 90% of the
bodies vitamin A is stored in the liver in fat tissues.
Betacarotene is a better source of vitamin A because it is non-
toxic, and also possesses antioxidant properties.
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