Postprandial glycemic response to 4-week low and high glycemic load diets

描述（由申请方提供）：本申请的总体目标是了解高血糖负荷与低血糖负荷膳食的餐后代谢反应。许多研究已经完成了餐后葡萄糖和胰岛素对不同血糖指数的个别食物的急性喂养的反应，但在人体研究中测量的大多数其他生物标志物是在空腹状态下进行的。关于膳食对生物标志物的影响知之甚少，这些生物标志物可能更直接地参与致癌途径，如胰岛素样生长因子。由于频繁进食和零食使许多美国人在醒着的许多时间里处于餐后状态，因此了解膳食对感兴趣的生物标志物的影响是一个重要但研究不足的研究领域。我们建议在20名参加随机交叉喂养研究的个体中测试对低血糖负荷和高血糖负荷膳食的餐后反应。在母研究中，参与者自由生活，但在两个四周的时间内从人类营养实验室获得所有食物和饮料。在一个喂养期，参与者被给予低血糖负荷饮食，而在另一个喂养期，参与者被给予高血糖负荷饮食。在每个喂养期的开始和结束时抽取空腹血液。对于这项拟议的研究，将邀请参与者在每个喂养期结束时额外进食两餐（早餐和午餐），然后连续抽血8小时，以评估胰岛素、葡萄糖、IGFI、IGDII、IGFBP 1、IGFBP 3、游离脂肪酸和甘油三酯的餐后反应。我们相信，这项拟议中的研究有效地利用了现有的良好控制的喂养研究，并将提供重要的信息，人类代谢反应的各种膳食模式。研究特定食物如何影响健康的一种方法是给人们喂食已知营养素含量的食物，并测量血液中的各种标志物。这项研究旨在比较低或高血糖负荷的膳食与已知与各种慢性疾病（如癌症）相关的各种生物标志物。参加随机交叉喂养研究的志愿者将被要求吃两顿额外的饭;我们将通过测量餐后8小时血液中的生物标志物来监测餐后反应。

DESCRIPTION (provided by applicant): The overall goal of this application is to understand the postprandial metabolic response to high vs. low glycemic load meals. Much research has been done on postprandial responses of glucose and insulin to acute feeding of individual foods of varying glycemic index, but most other biomarkers measured in human studies are done in the fasting state. Very little is known about meal effects on biomarkers that may be more directly in the carcinogenesis pathway, such as the insulin-like growth factors. Because frequent eating of meals and snacks places many Americans in the postprandial state for many of their waking hours, understanding meal effects on biomarkers of interest is an important, but understudied, area of research. We propose to test postprandial responses to low- and high-glycemic load meals in 20 individuals who are enrolled in a randomized, cross-over feeding study. In the parent study, participants are free-living but receive all food and beverages from a human nutrition laboratory for two four-week periods. During one feeding period participants are given a low-glycemic load diet and during the other a high glycemic load diet. Fasting bloods are drawn at the beginning and end of each feeding period. For this proposed study, participants will be invited to consume two extra meals (breakfast and lunch) at the end of each feeding period followed by eight hours of serial blood draws to assess the protracted postprandial response of insulin, glucose, IGFI, IGFII, IGFBP1, IGFBP3, free fatty acids, and triglycerides. We believe that this proposed study makes efficient use of an existing well-controlled feeding study and will provide important information on the human metabolic response to various meal patterns. Postprandial glycemic response to 4-week low and high glycemic load diets One way to study how specific foods affect health is to feed people meals with known quantities of nutrients and measure various markers in the blood. This study is designed to compare meals that are low- or high- glycemic load with respect to various biomarkers that are known to be related to various chronic diseases such as cancer. Volunteers enrolled in a randomized cross-over feeding study will be asked to eat two additional meals; we will monitor the postprandial responses by measuring biomarkers in the blood for eight hours after the meals.