Sex Differences in the Requirements of Certain Food Factors

1. On certain diets quoted in this paper, the male rat grows at about the same rate as the female, and does not show the more rapid growth which is usually exhibited by the male of the species. Finally the male becomes distinctly the heavier, but his growth is slow during the first weeks of life. 2. It is suggested that the growing male requires more vitamin B than the growing female, and also that he is more susceptible to the quality of the protein in the diet. The expenses of this research were defrayed by a grant from the Medical Research Council.