Gardner Christopher D, Lawson Larry D, Block Eric, Chatterjee Lorraine M, Kiazand Alexandre, Balise Raymond R, Kraemer Helena C
Stanford Prevention Research Center and Department of Medicine, Stanford University Medical School, Stanford, Calif 94305, USA.
Arch Intern Med. 2007 Feb 26;167(4):346-53. doi: 10.1001/archinte.167.4.346.
Garlic is widely promoted as a cholesterol-lowering agent, but efficacy studies have produced conflicting results. Garlic supplements differ in bioavailability of key phytochemicals. We evaluated the effect of raw garlic and 2 commonly used garlic supplements on cholesterol concentrations in adults with moderate hypercholesterolemia.
In this parallel-design trial, 192 adults with low-density lipoprotein cholesterol (LDL-C) concentrations of 130 to 190 mg/dL (3.36-4.91 mmol/L) were randomly assigned to 1 of the following 4 treatment arms: raw garlic, powdered garlic supplement, aged garlic extract supplement, or placebo. Garlic product doses equivalent to an average-sized garlic clove were consumed 6 d/wk for 6 months. The primary study outcome was LDL-C concentration. Fasting plasma lipid concentrations were assessed monthly. Extensive chemical characterization of study materials was conducted throughout the trial.
Retention was 87% to 90% in all 4 treatment arms, and chemical stability of study materials was high throughout the trial. There were no statistically significant effects of the 3 forms of garlic on LDL-C concentrations. The 6-month mean (SD) changes in LDL-C concentrations were +0.4 (19.3) mg/dL (+0.01 [0.50] mmol/L), +3.2 (17.2) mg/dL (+0.08 [0.44] mmol/L), +0.2 (17.8) mg/dL (+0.005 [0.46] mmol/L), and -3.9 (16.5) mg/dL (-0.10 [0.43] mmol/L) for raw garlic, powdered supplement, aged extract supplement, and placebo, respectively. There were no statistically significant effects on high-density lipoprotein cholesterol, triglyceride levels, or total cholesterol-high-density lipoprotein cholesterol ratio.
None of the forms of garlic used in this study, including raw garlic, when given at an approximate dose of a 4-g clove per day, 6 d/wk for 6 months, had statistically or clinically significant effects on LDL-C or other plasma lipid concentrations in adults with moderate hypercholesterolemia.
大蒜作为一种降胆固醇药物被广泛推广，但疗效研究结果相互矛盾。大蒜补充剂中关键植物化学物质的生物利用度存在差异。我们评估了生蒜和两种常用大蒜补充剂对中度高胆固醇血症成年人胆固醇浓度的影响。
在这项平行设计试验中，192名低密度脂蛋白胆固醇（LDL-C）浓度为130至190mg/dL（3.36 - 4.91mmol/L）的成年人被随机分配到以下4个治疗组之一：生蒜组、大蒜粉补充剂组、陈年大蒜提取物补充剂组或安慰剂组。相当于一瓣中等大小蒜瓣的大蒜产品剂量每周服用6天，共服用6个月。主要研究结局是LDL-C浓度。每月评估空腹血脂浓度。在整个试验过程中对研究材料进行了广泛的化学表征。
所有4个治疗组的保留率为87%至90%，并且在整个试验过程中研究材料的化学稳定性很高。三种形式的大蒜对LDL-C浓度均无统计学显著影响。生蒜组、大蒜粉补充剂组、陈年提取物补充剂组和安慰剂组LDL-C浓度6个月的平均（标准差）变化分别为+0.4（19.3）mg/dL（+0.01 [0.50] mmol/L）、+3.2（17.2）mg/dL（+0.08 [0.44] mmol/L）、+0.2（17.8）mg/dL（+0.005 [0.46] mmol/L）和 - 3.9（16.5）mg/dL（-0.10 [0.43] mmol/L）。对高密度脂蛋白胆固醇、甘油三酯水平或总胆固醇 - 高密度脂蛋白胆固醇比值均无统计学显著影响。
本研究中使用的任何形式的大蒜，包括生蒜，以每天约4克蒜瓣的剂量、每周6天、共6个月给药，对中度高胆固醇血症成年人的LDL-C或其他血脂浓度均无统计学或临床显著影响。
