Nantz Meri P, Rowe Cheryl A, Bukowski Jack F, Percival Susan S
Food Science and Human Nutrition Department, University of Florida, Gainesville, FL, USA.
Nutrition. 2009 Feb;25(2):147-54. doi: 10.1016/j.nut.2008.07.018. Epub 2008 Oct 9.
Previous studies examining the effect of tea drinking on cardiovascular health have produced mixed results due to their observational nature and qualitatively and quantitatively imprecise definitions of active tea components. The objective of this study was to determine if a standardized and defined decaffeinated green tea (Camellia sinensis) product lowers blood pressure, serum lipids, oxidative stress, and markers of chronic inflammation.
A randomized, double-blind, placebo-controlled, parallel study on 111 healthy adult volunteers 21-70 y old was performed. We administered a standardized capsule of Camellia sinensis compounds (CSC) twice a day. Before and after 3 wk, blood pressure, serum lipids, serum amyloid-alpha (a marker of chronic inflammation), and serum malondialdehyde (a marker of oxidative stress) were measured.
After 3 wk, CSC lowered systolic and diastolic blood pressures by 5 and 4 mmHg, respectively. After 3 mo, systolic blood pressure remained significantly lower. CSC lowered serum amyloid-alpha by 42% and lowered malondialdehyde by 11.9%. In men, there were 10- and 9-mg/dL reductions in total and low-density lipoprotein (LDL) cholesterol, respectively. In all subjects with a baseline LDL cholesterol level >99 mg/dL, there was 9 mg/dL lowering of total and LDL cholesterol. Adverse effects were mild and few and not different from placebo.
CSC was effective for decreasing, in as quickly as 3 wk, blood pressure, LDL cholesterol, oxidative stress, and a marker of chronic inflammation, all independent cardiovascular risk factors.
既往关于饮茶对心血管健康影响的研究由于其观察性本质以及活性茶成分在定性和定量方面定义不精确，结果不一。本研究的目的是确定一种标准化且明确的脱咖啡因绿茶（茶树）产品是否能降低血压、血脂、氧化应激以及慢性炎症标志物。
对111名年龄在21 - 70岁的健康成年志愿者进行了一项随机、双盲、安慰剂对照的平行研究。我们每天两次给予标准化的茶树化合物胶囊（CSC）。在3周前后，测量血压、血脂、血清淀粉样蛋白α（慢性炎症标志物）和血清丙二醛（氧化应激标志物）。
3周后，CSC使收缩压和舒张压分别降低了5 mmHg和4 mmHg。3个月后，收缩压仍显著降低。CSC使血清淀粉样蛋白α降低了42%，丙二醛降低了11.9%。在男性中，总胆固醇和低密度脂蛋白（LDL）胆固醇分别降低了10 mg/dL和9 mg/dL。在所有基线LDL胆固醇水平>99 mg/dL的受试者中，总胆固醇和LDL胆固醇降低了9 mg/dL。不良反应轻微且较少，与安慰剂无差异。
CSC可在短短3周内有效降低血压、LDL胆固醇、氧化应激以及慢性炎症标志物，这些都是独立的心血管危险因素。
