Jones P J, MacDougall D E, Ntanios F, Vanstone C A
School of Dietetics and Human Nutrition, McGill University, Montréal, QC, Canada.
Can J Physiol Pharmacol. 1997 Mar;75(3):217-27. doi: 10.1139/cjpp-75-3-217.
Phytosterols (plant sterols), abundant in fat-soluble fractions of plants, are consumed at levels of 200-400 mg/day in Western diets. Chemically resembling cholesterol, phytosterols inhibit the absorption of cholesterol. Phytosterol consumption in human subjects under a wide range of study conditions has been shown to reduce plasma total and low density lipoprotein (LDL) cholesterol levels; however, the response varies widely. Greater cholesterol-lowering efficacy occurs with consumption of the saturated phytosterol sitostanol versus sitosterol or campesterol. Most studies report no effect of phytosterol administration in high density lipoprotein (HDL) cholesterol or triglyceride levels, although certain evidence exists for an HDL cholesterol raising effect of sitostanol. Phytosterol absorption is limited, although serum phytosterol levels have proven to be important indicators of both cholesterol absorption and synthesis. Serum phytosterols correlate with HDL cholesterol level. In addition, higher phytosterol/cholesterol ratios appear in HDL versus LDL particles, suggesting the existence of an intrinsic phytosterol action, in addition to the extrinsic effect on cholesterol absorption. In conclusion, addition to diet of the phytosterol sitostanol represents an effective means of improving circulating lipid profiles to reduce risk of coronary heart disease.
植物甾醇（植物固醇）在植物的脂溶性部分中含量丰富，在西方饮食中，人们每天摄入的量为200 - 400毫克。植物甾醇在化学结构上与胆固醇相似，可抑制胆固醇的吸收。在广泛的研究条件下，人体受试者食用植物甾醇已被证明可降低血浆总胆固醇和低密度脂蛋白（LDL）胆固醇水平；然而，反应差异很大。与谷甾醇或菜油甾醇相比，食用饱和植物甾醇谷甾烷醇具有更强的降胆固醇功效。大多数研究报告称，服用植物甾醇对高密度脂蛋白（HDL）胆固醇或甘油三酯水平没有影响，不过有一定证据表明谷甾烷醇具有升高HDL胆固醇的作用。植物甾醇的吸收有限，尽管血清植物甾醇水平已被证明是胆固醇吸收和合成的重要指标。血清植物甾醇与HDL胆固醇水平相关。此外，HDL颗粒中的植物甾醇/胆固醇比值高于LDL颗粒，这表明除了对胆固醇吸收的外在影响外，还存在内在的植物甾醇作用。总之，在饮食中添加植物甾醇谷甾烷醇是改善循环脂质谱以降低冠心病风险的有效手段。
