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February 7, 1931


JAMA. 1931;96(6):444-445. doi:10.1001/jama.1931.02720320044012

The studies on the physiology of the vitamins have been concerned for the most part with a consideration of their ultimate nutritional effects and of the unmistakable manifestations of avitaminosis. The fate of these indispensable food factors in the body has received comparatively little attention. Theories of the precise mode in which the various known vitamins function still have little more than their authors' enthusiasms to commend them. Even the behavior of the vitamins at the portals of the organism, that is, in the alimentary tract, remains largely a matter of conjecture. There are indications that vitamins do not require digestive alteration in the sense in which proteins or polysaccharides necessitate digestive hydrolysis before they can be properly assimilated; for vitamin-bearing solutions have been employed effectively by introduction parenterally into the body. Koehne and Mendel,1 for example, observed in animal tests that both vitamins A and D in cod