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October 1959

Intermediary Metabolism of Phenylalanine and Tyrosine in Diffuse Collagen Diseases: II. Influences of the Low Phenylalanine and Tyrosine Diet upon Patients with Collagen Disease

Author Affiliations

Wakayama, Japan

Department of Dermatology & Urology, Wakayama Medical College.

AMA Arch Derm. 1959;80(4):466-477. doi:10.1001/archderm.1959.01560220076016

Previously, we1-3 reported the constant and specific presence of 2,5-dihydroxyphenylpyruvic acid, an imaginary intermediary metabolite of phenylalanine and tyrosine, in urine of diffuse collagen disease patients, and that L-tyrosine dosage unfailingly aggravated both clinical signs and laboratory data of collagen disease. Founded on these facts, low phenylalanine and tyrosine dietary treatment has been performed on 26 diffuse collagen disease patients with good results in both clinical signs and laboratory data.

Commonly, high-protein diet has been recommended for the treatments of collagen disease and also a few specific dietary treatments4-14 have been known.

Many investigators15-18 obtained good results in mental deficiency of phenylketonurics on well-defined synthetic diets deficient in phenylalanine.

Armstrong and Tyler and Woolf et al. suggested that the phenylalanine-restricted diet should be initiated at a very early age in order to prevent irreversible damage to the central nervous system.