Race Differences in the Ability to excrete Beetroot Pigment (Betanin)

Abstract

IT has been suggested that lack of betanin excretion in urine is a hereditary trait in man¹. This could result from an inborn incapacity to metabolize the pigment. This communication reports a study of the frequencies of betanin excretors among different racial groups. Classification of the excretors necessitated taking into account the time-range necessary for excretion, the amount of beetroot eaten and the pH of the urine. The effect of these variables on the validity of the test was determined before establishing the following procedure. 100–150 gm. of cooked beetroot was given to each individual examined. Two test-tube samples were taken, one before and the other 5 hr. after the beetroot was eaten. The classification of the individuals as excretors and non-excretors was based on visual comparison of the colour of the two urine samples. When any reddish tint could be observed in the second sample relative to the first the subject was recorded as ‘excretor’, and if otherwise, ‘non-excretor’. It should be noted that a great deal of variation was observed in the intensity of the red tint in the urine of the excretors.