LOW-CHO & HIGH-CHO, HIGH-FIBER DIETS & RISK MARKERS FOR THE METABOLIC SYNDROME

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 本研究的目的是比较低碳水化合物饮食与高碳水化合物、高纤维饮食（不强调热量限制）对代谢综合征患者胰岛素敏感性和心血管疾病风险的血液标志物的影响。 在一项随机交叉设计中，患有代谢综合征的男性和女性（即，与糖尿病和心脏病风险增加相关的代谢状况）将消耗两种饮食中的每一种：低碳水化合物饮食（15-20%碳水化合物; 55-60%脂肪; 25- 30%蛋白质）和高碳水化合物、高纤维饮食（55-60%碳水化合物; 20-25%脂肪; 15-20%蛋白质;每天> 30克纤维）。 每个饮食期将持续4周，其中有4-6周的洗脱期。 所有膳食将在一般临床研究中心（GCRC）厨房准备，每周三天由参与者领取，并将含有足够的热量来满足日常能量需求。 将指示受试者仅进食至不再饥饿，并将未食用的食物返还给GCRC。 我们假设高碳水化合物、高纤维饮食会显著改善胰岛素敏感性和增强心血管健康，而低碳水化合物饮食则不会。 结果测量包括胰岛素、葡萄糖、胆固醇、甘油三酯和几种炎症标志物的血液水平，以及检查前臂动脉内皮功能的超声程序。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The objective of this study is to compare a low-carbohydrate diet with high-carbohydrate, high-fiber diet-with no emphasis on calorie restriction--with regard to insulin sensitivity and blood markers for cardiovascular disease risk in men and women with the metabolic syndrome. In a randomized crossover design, men and women with the metabolic syndrome (i.e., a metabolic condition associated with increased risk for diabetes and heart disease) will consume each of two diets: a low-carbohydrate diet (15-20% carbohydrate; 55-60% fat; 25-30 protein) and a high-carbohydrate, high-fiber diet (55-60% carbohydrate; 20-25% fat; 15-20% protein; > 30 grams fiber per day). Each diet period will last 4 weeks, with a 4-6 week wash-out period. All meals will be prepared in the General Clinical Research Center (GCRC) kitchen for pick-up three days per week by the participants, and will contain more than enough calories to meet daily energy needs. Participants will be instructed to eat only until no longer hungry, and to return uneaten food to the GCRC. We hypothesize that that the high-carbohydrate, high-fiber diet will significantly improve insulin sensitivity and enhance cardiovascular health, and the low-carbohydrate diet will not. Outcome measures include blood levels of insulin, glucose, cholesterol, triglycerides, and several markers of inflammation, as well as an ultrasound procedure to examine endothelial function of a forearm artery.