{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T18:51:48Z","timestamp":1790794308598,"version":"4.1.0"},"reference-count":27,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2019,3,6]],"date-time":"2019-03-06T00:00:00Z","timestamp":1551830400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>We determined the serum uric acid-lowering effects of combined daily supplementation of glycine and tryptophan in patients with mild hyperuricemia using a randomized, double-blind, placebo-controlled, crossover clinical trial design. Japanese healthy adult males and females with mild hyperuricemia (fasting serum uric acid of 6.6\u20137.9 mg\/dL) ingested a powder mixture containing 3.0 g of glycine and 0.2 g of tryptophan or a placebo powder once daily at bedtime for 6 weeks. Combined supplementation with glycine and tryptophan significantly decreased serum uric acid levels (from 7.1 mg\/dL to 6.7 mg\/dL, p = 0.004) before and after the trial. Serum uric acid concentrations significantly decreased in the subjects supplemented with the amino acid mixture compared with those in placebo-treated subjects (p = 0.028). In addition, the combination treatment with glycine and tryptophan decreased serum triglyceride levels (from 119 mg\/dL to 86 mg\/dL, p = 0.002). Increased solubility of uric acid caused by urinary pH were likely contributors to the serum uric acid-lowering effects of the amino acid mixture.<\/jats:p>","DOI":"10.3390\/nu11030564","type":"journal-article","created":{"date-parts":[[2019,3,7]],"date-time":"2019-03-07T10:52:22Z","timestamp":1551955942000},"page":"564","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Serum Uric Acid-Lowering Effects of Combined Glycine and Tryptophan Treatments in Subjects with Mild Hyperuricemia: A Randomized, Double-Blind, Placebo-Controlled, Crossover Study"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1810-8661","authenticated-orcid":false,"given":"Shunji","family":"Oshima","sequence":"first","affiliation":[{"name":"Core Technology Laboratories, Asahi Group Holdings, Ltd., 1-21, Midori 1-Chome, Moriya-shi 302-0106, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sachie","family":"Shiiya","sequence":"additional","affiliation":[{"name":"Core Technology Laboratories, Asahi Group Holdings, Ltd., 1-21, Midori 1-Chome, Moriya-shi 302-0106, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yasunori","family":"Nakamura","sequence":"additional","affiliation":[{"name":"Core Technology Laboratories, Asahi Group Holdings, Ltd., 1-21, Midori 1-Chome, Moriya-shi 302-0106, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,3,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"160","DOI":"10.3389\/fmed.2018.00160","article-title":"Physiology of hyperuricemia and urate-lowering treatments","volume":"5","author":"Benn","year":"2018","journal-title":"Front. 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