To the Editor:—Is there available information concerning the medicinal use of yeast? How is it taken? I should like to know whether the use of it would cause any digestive disturbance, and whether the flesh gained is normal and permanent.
S. E. L., Bridgeport, Conn.
Answer.—Yeast is one of those remedies that have undergone alternating cycles of use and of disuse; just at present it appears again to be in its ascendency. No doubt, the reason for these cycles has been excessive praise and uncritical use, followed by disappointment and consequent discard.
Hawk and his associates (Hawk, P. B.; Knowles, F. C.; Rehfuss, M. E., and Clarke, J. A.: The Use of Bakers’ Yeast in Diseases of the Skin and of the Gastro-Intestinal Tract, The Journal, Oct. 13, 1917, p. 1243) have recently called renewed attention to its laxative qualities. When from one-half to one cake of yeast was given three times daily before meals, it produced regular bowel movements in a number of patients suffering from constipation. That this result is not due to any vital processes in the yeast is shown by the fact that yeast killed by boiling water was employed with success. It is suggested that such yeast might be preferred for patients troubled with flatulence. Aside from the tendency of living yeast to produce diarrhea, and the possibility that it may aggravate flatulence, no digestive disturbance has been charged against it. Aaron, in his “Diseases of the Digestive Organs,” speaks favorably of its use in atonic constipation.
The much debated question whether yeast may serve as a food can be answered in the affirmative in view of such work as that of the Germans on “Nährhefe”—yeast food (Schottelius, Deutsch. med. Wchnschr., July 8, 1915, p. 817) and Boruttau (ibid., July 29, 1915, p. 924) and of Hawk and his associates. There is no reason to assume that weight gained under its use would be more readily lost than weight gained from any other food. However, in view of its laxative action, the average individual can ingest only from 1 to 2 gm. of nitrogen a day in this form. This obviously greatly limits its value as a food. Owing to its high nuclein content, it is contraindicated in gout.
As a source of water soluble growth promoting as well as antineuritic vitamin, yeast has become thoroughly established as the result of the recent works of numerous investigators. However, as such common foods as milk, rice, wheat, oats and beans also contain such vitamin, there is little likelihood of its proving of therapeutic value on that account. In other words, yeast and other vitamin containing foods have specific growth promoting qualities only when the stunting is due to lack of vitamin. A minute amount of this substance suffices to produce maximal results. More is of no use. Hess (Proc. Soc. Exper. Biol. & Med. 13:145, 1916) found yeast of no value in infantile scurvy.
The most important question in connection with yeast therapy is to what extent it is endowed with “antibiotic” power, that is, to what degree it is capable of inhibiting the growth of other organisms. That this frequently occurs in cultures in vitro is shown by the fact that yeast contamination may practically eradicate the growth of certain other organisms. That, on the other hand, this is not true for all forms of bacterial life is shown by the fact that there is definite symbiosis between yeast and lactic acid bacilli (Northrup: Soc. Tech. Bull. 15, Mich. Agr. Expa. Sta., 1912).
That its “antiseptic power is, on the whole insignificant” has been shown by Palier (Diet. & Hyg. Gaz., March, 1906), who found commercial yeasts commonly contaminated with numerous bacteria, the most frequent being Bacillus coli-communis or one of its congeners. An antagonistic action by yeast is claimed against Staphylococcus pyogenes, and on the strength of this, Buchholtz (Ueber Acne und eine neue erfolgreiche Behandlung derselben, Berl. klin. Wchnschr., Feb. 2, 1914, p. 215) employed it locally in the treatment of acne and obtained a positive but temporary effect. He believes that the effect is improved by the combination of yeast with an equal quantity of boric acid. He employed this as a dusting powder applied freely to the skin once daily, after the application of a thin layer of a boric acid salve (boric acid powder from 40 to 50, glycerin and water, of each 100) to make it stick better. In cases in which the nose was markedly involved, he also used this as a snuff. Yeast poultices have been employed with asserted great benefit in the treatment of wound infection of all kinds (Kempf, E. J.: Ind. M. J., September, 1904, p. 97).
The use in leukorrhea was recommended by Hippocrates Abraham (Mon. Geb. Sym., 1910) and many others report favorable results from yeast in the treatment of gonorrheal vaginitis. In various gastro-intestinal infections, yeast has been lauded by many, among others, Thiercelin and Chevrey. It has been given by mouth, but most especially in high rectal enemas.
Still more from a theoretical standpoint is the reassertion of the curative value of the oral administration of yeast in various cutaneous disorders. Thus Hawk and his collaborators report cure or improvement in all of seventeen cases of acne vulgaris and eight cases of acne rosacea. They also report seventeen cases of furunculosis, in all but one of which there was cure or improvement from yeast treatment. They are unable to decide whether the result is due to the laxative action, the production of leukocytosis, or to other influences.