Black tea consumption dose-dependently improves flow-mediated dilation in healthy males
Black tea consumption dose-dependently improves flow-mediated dilation in healthy males
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DOI：
10.1097/hjh.0b013e328326066c
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发表时间：
2009-04-01
影响因子：
4.9
通讯作者：
Ferri, Claudio
中科院分区：
文献类型：
--
作者：
Grassi, Davide;Mulder, Theo P. J.;Ferri, Claudio
目的黄酮类化合物对心血管疾病具有保护作用。茶是膳食类黄酮的主要来源。研究表明，红茶可以改善内皮功能，但动脉血流动力学，血压（BP）和胰岛素抵抗的数据是模棱两可的。不一致可能是由于研究设计或测试的类黄酮剂量的缺陷。此外，没有研究评价剂量-反应曲线。方法采用随机、双盲、对照、交叉设计的方法，将19名健康男性分为5组，每天2次饮用红茶结果红茶剂量依赖性地使血流介导的舒张功能（FMD）从对照组的7.8%增加到对照组的9.0、9.1、9.2、9.1、9.2、9.3、9.4、9.5、9.6、9.7、9.8、9.9、9.6和10.3%（P = 0.0001）。与对照组相比，100 mg/天（少于1杯茶）已经增加了FMD（P = 0.0113）。与对照组相比，800 mg/天后的FMD改善显著（P < 0.0001），但与100 mg/天（P = 0.0121）和200 mg/天（P = 0.0275）相比也是如此。红茶摄入量降低办公室收缩压（-2.6mmHg，P = 0.0007）和舒张压（-2.2mmHg，P = 0.006）以及僵硬指数（P = 0.0159），而没有改变其他参数的研究。我们的数据表明，全世界所有喝茶的人都可以从茶的心血管保护作用中受益。J Hypertens 27：774-781（C）2009 Wolters Kluwer Health|利平科特威廉姆斯&威尔金斯。
Objectives Flavonoids may protect against cardiovascular disease. Tea is a major source of dietary flavonoids. Studies indicate black tea improves endothelial function but data on arterial haemodynamics, blood pressure (BP) and insulin resistance are equivocal. Inconsistency may be due to flaws in study design or flavonoid doses tested. Further, no study has evaluated the dose-response curve. Our study aimed to test the effects of various doses of black tea on vascular function, BP and insulin resistance.Methods According to a randomized, double-blind, controlled, cross-over design, 19 healthy men were assigned to receive either five treatments with a twice daily intake of black tea (0, 100, 200, 400 and 800 mg tea flvanoids/day) in five periods lasting 1 week each.Results Black tea dose dependently increased flow-mediated dilation (FMD) from 7.8% (control) to 9.0, 9.1, 9.6 and 10.3% after the different flavonoid doses, respectively (P = 0.0001). Already 100 mg/day (less than 1 cup of tea) increased FMD compared with control (P = 0.0113). FMD improvement after 800 mg/day was significant compared with control (P < 0.0001) but also to 100 mg/day (P = 0.0121) and 200 mg/day (P = 0.0275). Black tea intake decreased office systolic (-2.6 mmHg, P = 0.0007) and diastolic (-2.2 mmHg, P = 0.006) BP as well as stiffness index (P = 0.0159) without changes in other parameters studied.Conclusion Our study is the first showing black tea ingestion dose dependently improved FMD and decreased peripheral arterial stiffness in healthy volunteers. Our data suggest that worldwide all tea drinkers could benefit from protective cardiovascular effects exerted by tea. J Hypertens 27:774-781 (C) 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins.