There are about 50 different carotenes which can all be transformed into vitamin A if the body needs it. Betacarotene is the most important one. Often, it is the carotenoids that contribute to the yellow, orange, or red colours of flowers and fruits. Eating carrots every day for a long period of time, for example, can make your skin get a somewhat tanned appearance which is totally harmless. The colour will disappear if the consumption of carotene is reduced.
The vitamin A-effect of Betacarotene is 1/6 of the effect of real vitamin A.
1 mg. of betacarotene = 1,600 I.U. (International Units)