Shikany James M, Phadke Radhika P, Redden David T, Gower Barbara A
Division of Preventive Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294-4410, USA.
Metabolism. 2009 Dec;58(12):1793-801. doi: 10.1016/j.metabol.2009.06.006. Epub 2009 Jul 23.
Chronic insulin resistance contributes to subclinical inflammation, thrombosis/impaired fibrinolysis, and dyslipidemia. The effect of dietary carbohydrate, specifically of glycemic index (GI) and glycemic load (GL), on established and emerging coronary heart disease risk factors has not been elucidated fully. We conducted a randomized crossover feeding study of matched diets differing only in GI and GL in 24 overweight or obese but otherwise healthy men to investigate the effects on insulin sensitivity, inflammation, thrombosis/fibrinolysis, lipoproteins/lipids, and body composition. All meals for the high- and low-GI/GL diets were prepared in a metabolic kitchen. Each participant consumed both diets in random order for 4 weeks each, with a 4-week washout period in between. Each participant underwent a frequently sampled intravenous glucose tolerance test for assessment of insulin sensitivity; blood sampling for the measurement of inflammatory markers, coagulation factors, and lipoproteins/lipids; and dual-energy x-ray absorptiometry for assessment of body composition at the beginning and end of each dietary period. There were no statistically significant differences in glucose metabolism factors, inflammatory markers, or coagulation factors after 4 weeks on the high- and low-GI/GL diets. The high-GI/GL diet resulted in a slightly greater reduction in fat mass and a slightly greater increase in lean mass compared with the low-GI/GL diet. The high-GI/GL diet resulted in significant, but unexpected, reductions in total and low-density lipoprotein cholesterol, whereas high-density lipoprotein cholesterol concentration was significantly reduced on the high-GI/GL diet compared with the low-GI/GL diet. Overall, high- and low-GI/GL diets of 4 weeks' duration had no consistent effects on coronary heart disease risk factors in this group of overweight/obese men.
慢性胰岛素抵抗会导致亚临床炎症、血栓形成/纤维蛋白溶解受损和血脂异常。膳食碳水化合物，特别是血糖生成指数（GI）和血糖负荷（GL），对已确定的和新出现的冠心病危险因素的影响尚未完全阐明。我们对24名超重或肥胖但其他方面健康的男性进行了一项随机交叉喂养研究，研究仅在GI和GL方面不同的匹配饮食，以调查其对胰岛素敏感性、炎症、血栓形成/纤维蛋白溶解、脂蛋白/脂质和身体成分的影响。高GI/GL饮食和低GI/GL饮食的所有餐食均在代谢厨房制备。每位参与者以随机顺序分别食用两种饮食，每种饮食持续4周，中间有4周的洗脱期。每位参与者在每个饮食期开始和结束时都接受了频繁采样的静脉葡萄糖耐量试验以评估胰岛素敏感性；采集血样以测量炎症标志物、凝血因子和脂蛋白/脂质；并进行双能X线吸收法以评估身体成分。在高GI/GL饮食和低GI/GL饮食4周后，葡萄糖代谢因子、炎症标志物或凝血因子没有统计学上的显著差异。与低GI/GL饮食相比，高GI/GL饮食导致脂肪量的减少略多，瘦体重的增加略多。高GI/GL饮食导致总胆固醇和低密度脂蛋白胆固醇显著但出乎意料地降低，而与低GI/GL饮食相比，高GI/GL饮食中高密度脂蛋白胆固醇浓度显著降低。总体而言，为期4周的高GI/GL饮食和低GI/GL饮食对这组超重/肥胖男性的冠心病危险因素没有一致的影响。
