Institute of Human Nutrition and Food Science, Christian-Albrechts University, Kiel, Germany.
J Nutr. 2013 Oct;143(10):1593-601. doi: 10.3945/jn.113.179390. Epub 2013 Aug 14.
In this controlled, parallel-group feeding trial, we examined the impact of carbohydrate (CHO) intake and glycemic index (GI) on glucose and lipid metabolism during refeeding after weight loss. Healthy men (n = 32 total, age: 25.5 ± 3.9 y, BMI: 23.5 ± 2.0 kg/m2) overconsumed diets containing either 50% or 65% CHO for 1 wk (+50% of energy requirements) and then underwent 3 wk of calorie restriction (CR; -50%) followed by 2 wk of overconsuming (refeeding, +50%) the same diet but with either a low or high GI (40 vs.70 during CR, 41 vs.74 during refeeding) so that glycemic load (GL; dietary CHO content x GI) differed between groups during all phases. Glucose profiles were assessed by continuous interstitial glucose monitoring, insulin sensitivity (IS) by fasting blood sampling, oral glucose tolerance test (OGTT) and hyperinsulinemic-euglycemic clamp, and liver fat by MRI. Daytime area under the curve-glucose during refeeding was higher with high compared with low GI (P = 0.01) and 65% compared with 50% CHO intake (P = 0.05) and correlated with dietary GL (r = 0.71; P < 0.001). IS increased with CR and decreased again with refeeding in all groups. The decrease in OGTT-derived IS was greater with high- than with low-GI diets (-41 vs. -15%; P-interaction = 0.01) and correlated with dietary GL during refeeding (r = -0.51; P < 0.01). Serum triglycerides (TGs) and liver fat also improved with CR (-17 ± 38 mg/dL and -1.1 ± 1.3%; P < 0.05 and <0.001) and increased again with refeeding (+48 ± 48 mg/dL and +2.2 ± 1.6%; P < 0.001). After refeeding, serum TGs and liver fat were elevated above baseline values with 65% CHO intake only (+59.9 ± 37.5 mg/dL and +1.1 ± 1.7%, P-interaction <0.001 and <0.05). In conclusion, a diet low in GI and moderate in CHO content (i.e., low GL) may have health benefits by positively affecting daylong glycemia, IS, and liver fat.
在这项对照、平行组喂养试验中，我们研究了碳水化合物（CHO）摄入和血糖指数（GI）对减肥后再喂养期间葡萄糖和脂质代谢的影响。健康男性（共 32 人，年龄：25.5 ± 3.9 岁，BMI：23.5 ± 2.0 kg/m2）过量摄入 CHO 含量分别为 50%或 65%的饮食 1 周（+50%的能量需求），然后进行 3 周的热量限制（CR；-50%），然后再过量摄入（再喂养，+50%）相同的饮食，但 GI 不同（40 与 70 在 CR 期间，41 与 74 在再喂养期间），因此各组在所有阶段的血糖负荷（GL；饮食 CHO 含量 x GI）不同。通过连续间质葡萄糖监测评估葡萄糖谱，通过空腹采血、口服葡萄糖耐量试验（OGTT）和高胰岛素正葡萄糖钳夹评估胰岛素敏感性（IS），通过 MRI 评估肝脂肪。再喂养时，高 GI 组与低 GI 组（P = 0.01）和 65%CHO 组与 50%CHO 组（P = 0.05）相比，日间 AUC 葡萄糖更高，且与饮食 GL 呈正相关（r = 0.71；P < 0.001）。IS 在 CR 期间增加，在再喂养期间再次下降，所有组均如此。高 GI 组与低 GI 组相比，OGTT 衍生的 IS 下降幅度更大（-41%与-15%；P-交互=0.01），且与再喂养期间的饮食 GL 呈负相关（r =-0.51；P < 0.01）。血清甘油三酯（TGs）和肝脂肪也随着 CR 而改善（-17 ± 38 mg/dL 和-1.1 ± 1.3%；P < 0.05 和 <0.001），随着再喂养而再次增加（+48 ± 48 mg/dL 和+2.2 ± 1.6%；P < 0.001）。再喂养后，仅 65%CHO 摄入时血清 TGs 和肝脂肪高于基线值（+59.9 ± 37.5 mg/dL 和+1.1 ± 1.7%，P-交互<0.001 和 <0.05）。总之，低 GI 和中等 CHO 含量（即低 GL）的饮食可能通过积极影响全天血糖、IS 和肝脂肪来带来健康益处。
