Bonanome A, Grundy S M
Department of Clinical Nutrition, University of Texas Southwestern Medical Center, Dallas 75235-9052.
N Engl J Med. 1988 May 12;318(19):1244-8. doi: 10.1056/NEJM198805123181905.
We studied the metabolic effects of stearic acid (18:0) on plasma lipoprotein levels in 11 subjects during three dietary periods of three weeks each. The three liquid-formula diets, which were used in random order, were high in palmitic acid (16:0), stearic acid, and oleic acid (18:1), respectively. Caloric intakes were the same during the three periods. As compared with the values observed when the subjects were on the high-palmitic-acid diet, plasma total cholesterol decreased by an average of 14 percent during consumption of the high-stearic-acid diet (P less than 0.005) and by 10 percent during consumption of the high-oleic-acid diet (P less than 0.02). Low-density lipoprotein cholesterol levels fell by 21 percent in subjects on the high-stearic-acid diet (P less than 0.005) and by 15 percent in subjects on the high-oleic-acid diet (P less than 0.005). No significant differences were observed in the plasma levels of triglycerides or high-density lipoprotein cholesterol among the three diets. Measurements of the intestinal absorption of palmitic, stearic, and oleic acids revealed essentially complete absorption of each during the three dietary periods. The oleic acid content of plasma triglycerides and cholesteryl esters increased significantly during the high-stearic-acid period, suggesting that stearic acid is rapidly converted to oleic acid. We conclude that stearic acid appears to be as effective as oleic acid in lowering plasma cholesterol levels when either replaces palmitic acid in the diet.
我们研究了硬脂酸（18:0）对11名受试者血浆脂蛋白水平的代谢影响，研究为期三个阶段，每个阶段为期三周。三种液体配方饮食以随机顺序使用，分别富含棕榈酸（16:0）、硬脂酸和油酸（18:1）。三个阶段的热量摄入相同。与受试者食用高棕榈酸饮食时观察到的值相比，食用高硬脂酸饮食期间血浆总胆固醇平均下降了14%（P<0.005），食用高油酸饮食期间下降了10%（P<0.02）。高硬脂酸饮食组受试者的低密度脂蛋白胆固醇水平下降了21%（P<0.005），高油酸饮食组受试者的低密度脂蛋白胆固醇水平下降了15%（P<0.005）。三种饮食之间的血浆甘油三酯或高密度脂蛋白胆固醇水平未观察到显著差异。对棕榈酸、硬脂酸和油酸肠道吸收的测量显示，在三个饮食阶段中，每种酸的吸收基本完全。在高硬脂酸阶段，血浆甘油三酯和胆固醇酯中的油酸含量显著增加，这表明硬脂酸能迅速转化为油酸。我们得出结论，当饮食中的棕榈酸被硬脂酸或油酸替代时，硬脂酸在降低血浆胆固醇水平方面似乎与油酸一样有效。
