The Basal-metabolic Rates of Vegetarians.

The work of Benedict and Roth (l), published in 1913, indicated that there is little if any consistent difference between the basal metabolic rates of vegetarians and non-vegetarians. It was only after observing several cases of surprisingly low basal metabolic rates in vegetarian girls of normal health and intelligence that the writers of the present paper concluded that the length of the period of vegetarianism might be a factor in determining the basal metabolic rate. The specific dynamic action of proteins is a generally recognized effect. The immediate influences of sudden changes in protein ration upon basal metabolic rates have, however. been conflictingly reported. Perhaps the most spectacular case in recent literature is that of Wishart (2) who observed, in his own case, an increase of 50 per cent in his basal metabolic rate after changing from a daily protein ration of 30 gm. to one of 150 gm. He confessed, however, that the application of his ingenious formula “to the prediction of the basal metabolism of a number of individuals . . . met with little success.” Wang and Hawks, in their excellent review of the whole subject (3), after citing the somewhat conflicting evidence of Kleitman (4), Wishart (2, 5), Deuel et al. (6), and others, “failed to find any noticeable difference in the basal heat production in a careful study of the influence of high and low protein diets on the metabolic changes in six normal adult women.” The junior author of this paper (L. 0. H), working on himself, reached a similar conclusion. The object of the work recorded in the present paper was to determine whether long periods of vegetarianism could be shown to have any consistent effect upon average basal met’abolic rates. The difficulties usually encountered in obtaining the services of a