Ginsberg H N, Kris-Etherton P, Dennis B, Elmer P J, Ershow A, Lefevre M, Pearson T, Roheim P, Ramakrishnan R, Reed R, Stewart K, Stewart P, Phillips K, Anderson N
Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA.
Arterioscler Thromb Vasc Biol. 1998 Mar;18(3):441-9. doi: 10.1161/01.atv.18.3.441.
Few well-controlled diet studies have investigated the effects of reducing dietary saturated fatty acid (SFA) intake in premenopausal and postmenopausal women or in blacks. We conducted a multicenter, randomized, crossover-design trial of the effects of reducing dietary SFA on plasma lipids and lipoproteins in 103 healthy adults 22 to 67 years old. There were 46 men and 57 women, of whom 26 were black, 18 were postmenopausal women, and 16 were men > or =40 years old. All meals and snacks, except Saturday dinner, were prepared and served by the research centers. The study was designed to compare three diets: an average American diet (AAD), a Step 1 diet, and a low-SFA (Low-Sat) diet. Dietary cholesterol was constant. Diet composition was validated and monitored by a central laboratory. Each diet was consumed for 8 weeks, and blood samples were obtained during weeks 5 through 8. The compositions of the three diets were as follows: AAD, 34.3% kcal fat and 15.0% kcal SFA; Step 1, 28.6% kcal fat and 9.0% kcal SFA; and Low-Sat, 25.3% kcal fat and 6.1% kcal SFA. Each diet provided approximately 275 mg cholesterol/d. Compared with AAD, plasma total cholesterol in the whole group fell 5% on Step 1 and 9% on Low-Sat. LDL cholesterol was 7% lower on Step 1 and 11% lower on Low-Sat than on the AAD (both P<.01). Similar responses were seen in each subgroup. HDL cholesterol fell 7% on Step 1 and 11% on Low-Sat (both P<.01). Reductions in HDL cholesterol were seen in all subgroups except blacks and older men. Plasma triglyceride levels increased approximately 9% between AAD and Step 1 but did not increase further from Step 1 to Low-Sat. Changes in triglyceride levels were not significant in most subgroups. Surprisingly, plasma Lp(a) concentrations increased in a stepwise fashion as SFA was reduced. In a well-controlled feeding study, stepwise reductions in SFA resulted in parallel reductions in plasma total and LDL cholesterol levels. Diet effects were remarkably similar in several subgroups of men and women and in blacks. The reductions in total and LDL cholesterol achieved in these different subgroups indicate that diet can have a significant impact on risk for atherosclerotic cardiovascular disease in the total population.
很少有严格控制的饮食研究调查过减少绝经前和绝经后女性或黑人饮食中饱和脂肪酸（SFA）摄入量的影响。我们进行了一项多中心、随机、交叉设计试验，研究减少饮食中SFA对103名22至67岁健康成年人血浆脂质和脂蛋白的影响。其中有46名男性和57名女性，其中26人为黑人，18人为绝经后女性，16名男性年龄≥40岁。除周六晚餐外，所有餐食和零食均由研究中心准备和提供。该研究旨在比较三种饮食：美国平均饮食（AAD）、第一步饮食和低SFA（低饱和）饮食。饮食中的胆固醇含量保持不变。饮食成分由中央实验室进行验证和监测。每种饮食持续食用8周，并在第5至8周采集血样。三种饮食的成分如下：AAD，34.3%千卡脂肪和15.0%千卡SFA；第一步饮食，28.6%千卡脂肪和9.0%千卡SFA；低饱和饮食，25.3%千卡脂肪和6.1%千卡SFA。每种饮食每天提供约275毫克胆固醇。与AAD相比，整个组的血浆总胆固醇在第一步饮食时下降了5%，在低饱和饮食时下降了9%。第一步饮食时低密度脂蛋白胆固醇比AAD低7%，低饱和饮食时低11%（两者P<0.01）。在每个亚组中都观察到了类似的反应。高密度脂蛋白胆固醇在第一步饮食时下降了7%，在低饱和饮食时下降了11%（两者P<0.01）。除黑人和老年男性外，所有亚组的高密度脂蛋白胆固醇均有下降。从AAD到第一步饮食，血浆甘油三酯水平大约升高了9%，但从第一步饮食到低饱和饮食时没有进一步升高。大多数亚组中甘油三酯水平的变化不显著。令人惊讶的是，随着SFA的减少，血浆Lp(a)浓度呈逐步上升趋势。在一项严格控制的喂养研究中，SFA的逐步减少导致血浆总胆固醇和低密度脂蛋白胆固醇水平平行下降。男性和女性的几个亚组以及黑人中的饮食效果非常相似。在这些不同亚组中实现的总胆固醇和低密度脂蛋白胆固醇的降低表明，饮食对整个人群的动脉粥样硬化性心血管疾病风险可能有重大影响。
