The effect of tocopherol on the utilisation of intravenously administered carotene

Summary The effect of tocopherol on the conversion of intravenously administered aqueous dispersions of carotene in Tween 40 (polyoxyethylene‐ sorbitan monopalmitate) has been further investigated. High levels of tocopherol in the blood and tissues have been found to inhibit the conversion of carotene to vitamin A and on the basis of results obtained with preliminary, simultaneous, and subsequent injections of tocopherol, it is concluded that intravenously administered carotene undergoes a rapid breakdowr. possibly in the blood, to an intermediate which is then more slowly converted to vitamin A.