An Experimental Study of Brown and White Bread in the Diet of the Rat

THE question of the superiority of brown over white bread has been the subject of many discussions. A number of people assume that brown bread has a far greater dietetic value than white bread, but there are very few experimental data to warrant such an assumption. Perhaps the point most usually quoted in favour of brown bread is its vitamin B content. It is frequently stated that white bread' is lacking in this factor, and therefore brown bread must be the better food. That this is not so, was shown by the author in a previous communication [1924, 1]. In this paper experiments were described in which rats were kept for as long as a year on a diet of white bread, butter and salt mixture. The animals showed no symptoms indicative of lack of vitamin B, the only source of which was the white bread. From a common- sense point of view, also, it seems ridiculous to state that white bread contains no vitamin B, when yeast, used in the manufacture of white bread, is accepted as being one of the richest sources of this vitamin. From information obtained from various bakers, it is found that the amount of yeast used in bread manu- facture is by no means the minute amount accepted by the general public, but varies from 2-8 % of the flour used. It is not claimed that the vitamin B