O'Dea K, Traianedes K, Chisholm K, Leyden H, Sinclair A J
Department of Human Nutrition, Deakin University.
Am J Clin Nutr. 1990 Sep;52(3):491-4. doi: 10.1093/ajcn/52.3.491.
The aim of this study was to differentiate between lean beef and beef fat as risk factors for elevated plasma cholesterol concentrations. Ten healthy weight-stable subjects (five men, five women) participated. Energy intake was kept constant over the 5-wk study. Total cholesterol concentrations fell significantly within 1 wk of commencing the very-low fat (9%) energy from fat) lean-beef (500 g/d) diet (5.91 +/- 0.47 to 4.72 +/- 0.42 mmol/L, p less than 0.001) and rose as beef drippings were added in a stepwise manner in weeks 4 and 5 (5.45 +/- 0.56 mmol/L in week 5). The changes in total cholesterol concentrations were due almost entirely to changes in the concentration of low-density lipoprotein cholesterol levels. These results indicate that it is the beef fat, not lean beef itself, that is associated with elevations in cholesterol concentrations and that lean beef can be included in cholesterol-lowering diets provided it is free of all visible fat and the saturated fatty acid content of the diet is low.
本研究的目的是区分瘦牛肉和牛肉脂肪作为血浆胆固醇浓度升高的风险因素。十名体重稳定的健康受试者（五名男性，五名女性）参与了研究。在为期5周的研究中，能量摄入保持恒定。开始极低脂肪（脂肪供能占9%）的瘦牛肉（500克/天）饮食后1周内，总胆固醇浓度显著下降（从5.91±0.47降至4.72±0.42毫摩尔/升，p<0.001），并在第4周和第5周逐步添加牛肉脂肪滴时上升（第5周为5.45±0.56毫摩尔/升）。总胆固醇浓度的变化几乎完全归因于低密度脂蛋白胆固醇水平的变化。这些结果表明，与胆固醇浓度升高相关的是牛肉脂肪，而非瘦牛肉本身；并且只要瘦牛肉不含所有可见脂肪且饮食中的饱和脂肪酸含量较低，就可以纳入降胆固醇饮食中。
