Hu F B, Stampfer M J, Manson J E, Rimm E, Colditz G A, Rosner B A, Hennekens C H, Willett W C
Department of Nutrition, Harvard School of Public Health, Boston, MA 02115, USA.
N Engl J Med. 1997 Nov 20;337(21):1491-9. doi: 10.1056/NEJM199711203372102.
The relation between dietary intake of specific types of fat, particularly trans unsaturated fat and the risk of coronary disease remains unclear. We therefore studied this relation in women enrolled in the Nurses' Health Study.
We prospectively studied 80,082 women who were 34 to 59 years of age and had no known coronary disease, stroke, cancer, hypercholesterolemia, or diabetes in 1980. Information on diet was obtained at base line and updated during follow-up by means of validated questionnaires. During 14 years of follow-up, we documented 939 cases of nonfatal myocardial infarction or death from coronary heart disease. Mutivariate analyses included age, smoking status, total energy intake, dietary cholesterol intake, percentages of energy obtained from protein and specific types of fat, and other risk factors.
Each increase of 5 percent of energy intake from saturated fat, as compared with equivalent energy intake from carbohydrates, was associated with a 17 percent increase in the risk of coronary disease (relative risk, 1.17; 95 percent confidence interval, 0.97 to 1.41; P=0.10). As compared with equivalent energy from carbohydrates, the relative risk for a 2 percent increment in energy intake from trans unsaturated fat was 1.93 (95 percent confidence interval, 1.43 to 2.61; P<0.001); that for a 5 percent increment in energy from monounsaturated fat was 0.81 (95 percent confidence interval, 0.65 to 1.00; P=0.05); and that for a 5 percent increment in energy from polyunsaturated fat was 0.62 (95 percent confidence interval, 0.46 to 0.85; P= 0.003). Total fat intake was not signficantly related to the risk of coronary disease (for a 5 percent increase in energy from fat, the relative risk was 1.02; 95 percent confidence interval, 0.97 to 1.07; P=0.55). We estimated that the replacement of 5 percent of energy from saturated fat with energy from unsaturated fats would reduce risk by 42 percent (95 percent confidence interval, 23 to 56; P<0.001) and that the replacement of 2 percent of energy from trans fat with energy from unhydrogenated, unsaturated fats would reduce risk by 53 percent (95 percent confidence interval, 34 to 67; P<.001).
Our findings suggest that replacing saturated and trans unsaturated fats with unhydrogenated monounsaturated and polyunsaturated fats is more effective in preventing coronary heart disease in women than reducing overall fat intake.
特定类型脂肪的膳食摄入量，尤其是反式不饱和脂肪与冠心病风险之间的关系仍不明确。因此，我们在参加护士健康研究的女性中研究了这种关系。
我们前瞻性地研究了80082名年龄在34至59岁之间、1980年时无已知冠心病、中风、癌症、高胆固醇血症或糖尿病的女性。通过经过验证的问卷在基线时获取饮食信息，并在随访期间更新。在14年的随访中，我们记录了939例非致命性心肌梗死或冠心病死亡病例。多变量分析包括年龄、吸烟状况、总能量摄入、膳食胆固醇摄入、从蛋白质和特定类型脂肪中获取的能量百分比以及其他风险因素。
与从碳水化合物中摄入等量能量相比，饱和脂肪能量摄入量每增加5%，冠心病风险增加17%（相对风险为1.17；95%置信区间为0.97至1.41；P = 0.10）。与从碳水化合物中摄入等量能量相比，反式不饱和脂肪能量摄入量增加2%时的相对风险为1.93（95%置信区间为1.43至2.61；P < 0.001）；单不饱和脂肪能量增加5%时的相对风险为0.81（95%置信区间为0.65至1.00；P = 0.05）；多不饱和脂肪能量增加5%时的相对风险为0.62（95%置信区间为0.46至0.85；P = 0.003）。总脂肪摄入量与冠心病风险无显著相关性（脂肪能量增加5%时，相对风险为1.02；95%置信区间为0.97至1.07；P = 0.55）。我们估计，用不饱和脂肪替代5%的饱和脂肪能量可使风险降低42%（95%置信区间为23至56；P < 0.001），用未氢化的不饱和脂肪替代2%的反式脂肪能量可使风险降低53%（95%置信区间为34至67；P < 0.001）。
我们的研究结果表明，用未氢化的单不饱和脂肪和多不饱和脂肪替代饱和脂肪和反式不饱和脂肪在预防女性冠心病方面比减少总脂肪摄入量更有效。
