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Double-blind, placebo-controlled pilot trial of anthocyanin-rich purple sweet potato beverage on serum hepatic biomarker levels in healthy Caucasians with borderline hepatitis


The objective is to evaluate the efficacy of anthocyanin-rich purple-fleshed sweet potato (PSP) beverage on the serum levels of gamma-glutamyl transferase (GGT), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in healthy Caucasians with borderline hepatitis. Forty healthy Caucasians (41–69 years) consumed three bottles of the PSP beverage (177 mg anthocyanins per 125-ml bottle) or placebo (1.3 mg) per day for 8 weeks. Thirty-nine subjects completed the study and two subjects were excluded from statistical analysis. GGT levels in the PSP group on days 15 and 43 were lower (P=0.077 and 0.038, respectively), AST levels in the PSP group on days 29 and 43 were lower (P=0.010 and 0.045, respectively) and ALT level in the PSP group on day 43 was lower (P=0.037) than in the placebo group. The PSP beverage did not induce clinically relevant changes in other blood and clinical chemistry parameters.

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This study was supported by a Grant-in-Aid for Research and Development Projects for Application in Promoting New Policy of Agriculture Forestry and Fisheries (Grant Number: 1922) from the Ministry of Agriculture, Forestry and Fisheries (MAFF) of Japan. We are grateful to O. Yamakawa, Ph.D., for discussions and advice throughout this study.

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Correspondence to T Oki.

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Oki, T., Kano, M., Ishikawa, F. et al. Double-blind, placebo-controlled pilot trial of anthocyanin-rich purple sweet potato beverage on serum hepatic biomarker levels in healthy Caucasians with borderline hepatitis. Eur J Clin Nutr 71, 290–292 (2017).

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