College of Health Solutions, Arizona State University, Phoenix, AZ 85004, USA.
Soriant Solutions, Roswell, GA 30075, USA.
Nutrients. 2019 Oct 6;11(10):2387. doi: 10.3390/nu11102387.
Both glycemic index and dietary fiber are associated with cardiovascular disease risk, which may be related in part to postprandial vascular effects. We examined the effects of both glycemic index (GI) and dietary (mainly cereal) fiber on postprandial endothelial function. Eleven adults (5 men; 6 women; age = 42.4 ± 16.1 years; weight = 70.5 ± 10.7 kg; height = 173.7 ± 8.7 cm) consumed four different breakfast meals on separate, randomized occasions: High-Fiber, Low-GI (HF-LGI: Fiber = 20.4 g; GI = 44); Low-Fiber, Low-GI (LF-LGI: Fiber = 4.3 g; GI = 43); Low-Fiber, High-GI (LF-HGI: Fiber = 3.6 g; GI = 70); High-Fiber, High-GI (HF-HGI: Fiber = 20.3 g; GI = 71). Meals were equal in total kcal (600) and macronutrient composition (90 g digestible carbohydrate; ~21 g protein; ~15 g fat). The HF-LGI meal resulted in a significant increase in flow-mediated dilation (FMD) 4 hours after meal ingestion (7.8% ± 5.9% to 13.2% ± 5.5%; = 0.02). FMD was not changed after the other meals. Regardless of fiber content, low-GI meals resulted in ~9% lower 4-hour glucose area under curve (AUC) ( < 0.05). The HF-LGI meal produced the lowest 4-hour insulin AUC, which was ~43% lower than LF-HGI and HF-HGI ( < 0.001), and 28% lower than LF-LGI ( = 0.02). We conclude that in healthy adults, a meal with low GI and high in cereal fiber enhances postprandial endothelial function. Although the effect of a low-GI meal on reducing postprandial glucose AUC was independent of fiber, the effect of a low-GI meal on reducing postprandial insulin AUC was augmented by cereal fiber.
血糖指数和膳食纤维都与心血管疾病风险相关，这可能部分与餐后血管效应有关。我们研究了血糖指数（GI）和膳食纤维（主要是谷物纤维）对餐后内皮功能的影响。11 名成年人（5 名男性；6 名女性；年龄=42.4±16.1 岁；体重=70.5±10.7kg；身高=173.7±8.7cm）分别在不同的随机时间内食用了四种不同的早餐：高纤维、低 GI（HF-LGI：纤维=20.4g；GI=44）；低纤维、低 GI（LF-LGI：纤维=4.3g；GI=43）；低纤维、高 GI（LF-HGI：纤维=3.6g；GI=70）；高纤维、高 GI（HF-HGI：纤维=20.3g；GI=71）。这些餐食的总热量（约 600 卡路里）和宏量营养素组成（约 90 克可消化碳水化合物；21 克蛋白质；15 克脂肪）基本相同。HF-LGI 餐在餐后 4 小时可显著增加血流介导的扩张（FMD）（7.8%±5.9%至 13.2%±5.5%；=0.02）。其他餐食后 FMD 没有变化。无论纤维含量如何，低 GI 餐可使餐后 4 小时血糖 AUC 降低约 9%（<0.05）。HF-LGI 餐的餐后 4 小时胰岛素 AUC 最低，比 LF-HGI 和 HF-HGI 低约 43%（<0.001），比 LF-LGI 低 28%（=0.02）。我们的结论是，在健康成年人中，低 GI 且富含谷物纤维的膳食可增强餐后内皮功能。虽然低 GI 餐对降低餐后血糖 AUC 的作用与纤维无关，但低 GI 餐对降低餐后胰岛素 AUC 的作用因谷物纤维而增强。
