Journal of Functional Foods (Oct 2022)

Ameliorating prediabetic subject status via fermented tea supplementation: A randomized, double-blind, parallel-group comparison study

  • Yasufumi Katanasaka,
  • Yoichi Sunagawa,
  • Yusuke Miyazaki,
  • Masafumi Funamoto,
  • Satoshi Shimizu,
  • Kana Shimizu,
  • Hajime Yamakage,
  • Noriko Satoh-Asahara,
  • Kazushige Toyama,
  • Toru Sabashi,
  • Mika Suzuki,
  • Toshihide Hamabe-Horiike,
  • Maki Komiyama,
  • Hiromichi Wada,
  • Kiyoshi Mori,
  • Koji Hasegawa,
  • Tatsuya Morimoto

Journal volume & issue
Vol. 97
p. 105257

Abstract

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Fermented tea consumption has been reported to alleviate diabetes and dyslipidemia, inducing an antiobesity effect. Here, we investigated the effects of microbial fermented tea and microbial fermented twig tea, which are made from Camellia sinensis by fermentation with Aspergillus sp., on glucose tolerance and metabolic syndrome in prediabetic subjects in a randomized, double-blind study. They were asked to consume the tea three times a day for 12 weeks. Fasting blood glucose, HbA1c, and 2-h oral glucose tolerance test (OGTT) were measured as primary endpoints. After 12 weeks, fasting blood glucose level was significantly reduced in the microbial fermented twig tea group (n = 19) as compared with that in the microbial fermented tea group (n = 16, p = 0.017). There was no significant difference in the 2-hour OGTT and HbA1c values between the two groups. Triglyceride levels were significantly lower in the microbial fermented tea group than in the microbial fermented twig tea group at 12 weeks (p = 0.049).

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