Because yeast can be substituted successfully for part of the protein requirements of an adult,1 is nontoxic,2 will apparanently improve skin diseases in adults,3 cure polyneuritis in pigeons,4 and cause rats on an inadequate diet to gain in weight,5 numerous advertisements in the non-medical press have acclaimed that yeast in various forms is a panacea for the ills of man and that even infants would be improved by a tablet or two a day. That this conclusion is falsely derived from inapplicable premises is proven not only by the elementary rules of logic, but, furthermore, experiments6 have shown that when applied to infants, yeast therapy is not only without benefit but may actually do harm. The evidence reported here merely confirms these latter publications.
Demonstrations of the value of vitamin therapy in the feeding of normal infants are not convincing7 for the majority
DAVISON WC. THE FAILURE OF YEAST THERAPY IN THE FEEDING OF INFANTS. Am J Dis Child. 1922;24(4):339-345. doi:10.1001/archpedi.1922.04120100072008