Gardner Christopher D, Coulston Ann, Chatterjee Lorraine, Rigby Alison, Spiller Gene, Farquhar John W
Stanford University Medical School and Stanford University Medical Center, Stanford, California, USA.
Ann Intern Med. 2005 May 3;142(9):725-33. doi: 10.7326/0003-4819-142-9-200505030-00007.
A variety of food combinations can be used to meet national U.S. guidelines for obtaining 30% of energy or less from total fat and 10% of energy or less from saturated fat.
To contrast plasma lipid responses to 2 low-fat diet patterns.
Randomized clinical trial.
4-week outpatient feeding study with weight held constant.
120 adults 30 to 65 years of age with prestudy low-density lipoprotein (LDL) cholesterol concentrations of 3.3 to 4.8 mmol/L (130 to 190 mg/dL), body mass index less than 31 kg/m2, estimated dietary saturated fat at least 10% of calories, and otherwise general good health.
Plasma lipid levels.
Two diets, the Low-Fat diet and the Low-Fat Plus diet, designed to be identical in total fat, saturated fat, protein, carbohydrate, and cholesterol content, consistent with former American Heart Association Step I guidelines. The Low-Fat diet was relatively typical of a low-fat U.S. diet. The Low-Fat Plus diet incorporated considerably more vegetables, legumes, and whole grains, consistent with the 2000 American Heart Association revised guidelines.
Four-week changes in the Low-Fat and Low-Fat Plus groups were -0.24 mmol/L (-9.2 mg/dL) versus -0.46 mmol/L (-17.6 mg/dL) for total cholesterol (P = 0.01) and -0.18 mmol/L (-7.0 mg/dL) versus -0.36 mmol/L (-13.8 mg/dL) for LDL cholesterol (P = 0.02); between-group differences were -0.22 mmol/L (-9 mg/dL) (95% CI, -0.05 to -0.39 mmol/L [-2 to -15 mg/dL]) and -0.18 mmol/L (-7 mg/dL) (CI, -0.04 to -0.32 mmol/L [-2 to -12 mg/dL]) for total and LDL cholesterol, respectively. The 2 diet groups did not differ significantly in high-density lipoprotein cholesterol and triglyceride levels.
4-week duration.
Previous national dietary guidelines primarily emphasized avoiding saturated fat and cholesterol; as a result, the guidelines probably underestimated the potential LDL cholesterol-lowering effect of diet. In this study, emphasis on including nutrient-dense plant-based foods, consistent with recently revised national guidelines, increased the total and LDL cholesterol-lowering effect of a low-fat diet.
多种食物组合可用于满足美国国家指南中关于总脂肪摄入量占能量的30%或更低、饱和脂肪摄入量占能量的10%或更低的要求。
对比两种低脂饮食模式对血浆脂质的反应。
随机临床试验。
为期4周的门诊喂养研究，体重保持恒定。
120名年龄在30至65岁之间的成年人，研究前低密度脂蛋白（LDL）胆固醇浓度为3.3至4.8 mmol/L（130至190 mg/dL），体重指数小于31 kg/m²，估计饮食中饱和脂肪至少占卡路里的10%，且总体健康状况良好。
血浆脂质水平。
两种饮食，即低脂饮食和低脂加饮食，设计为总脂肪、饱和脂肪、蛋白质、碳水化合物和胆固醇含量相同，符合美国心脏协会先前的第一步指南。低脂饮食相对典型的是美国低脂饮食。低脂加饮食包含了更多的蔬菜、豆类和全谷物，符合2000年美国心脏协会修订指南。
低脂组和低脂加组四周内总胆固醇变化分别为−0.24 mmol/L（−9.2 mg/dL）和−0.46 mmol/L（−17.6 mg/dL）（P = 0.01），低密度脂蛋白胆固醇变化分别为−0.18 mmol/L（−7.0 mg/dL）和−0.36 mmol/L（−13.8 mg/dL）（P = 0.02）；总胆固醇和低密度脂蛋白胆固醇的组间差异分别为−0.22 mmol/L（−9 mg/dL）（95% CI，−0.05至−0.39 mmol/L [−2至−15 mg/dL]）和−0.18 mmol/L（−7 mg/dL）（CI，−0.04至−0.32 mmol/L [−2至−12 mg/dL]）。两组在高密度脂蛋白胆固醇和甘油三酯水平上无显著差异。
为期4周。
先前的国家饮食指南主要强调避免饱和脂肪和胆固醇；因此，这些指南可能低估了饮食对低密度脂蛋白胆固醇的潜在降低作用。在本研究中，按照最近修订的国家指南，强调纳入营养丰富的植物性食物，增强了低脂饮食对总胆固醇和低密度脂蛋白胆固醇的降低作用。
