Dietary Fiber and Cardiovascular Inflammatory Markers

描述(申请人提供)：本研究的目的是调查膳食纤维与心血管炎症标志物之间的关系。最近的研究发现，高纤维摄入量的饮食与心血管疾病(CVD)的减少有关。然而，该协会并没有证明膳食纤维实际上是降低心血管疾病风险的原因，也没有阐明潜在的降低风险的机制(如果存在)。由于饮食与心血管疾病有很强的联系，并且鉴于心血管疾病是发病率和死亡率的主要因素，更多的信息将是有价值的。我们的初步研究和其他人的工作表明，C-反应蛋白(CRP)和膳食纤维摄入量之间存在显著的关联。这些观察结果使我们得出了以下统一的假设：高纤维饮食与较低水平的炎症标志物相关。我们的长期目标是确定炎症是否是纤维摄入和心血管疾病风险之间联系的关键中介。该项目的三个具体目标是：1：在1999-2000年全国健康和营养检查调查中，确定总膳食纤维和/或纤维补充剂是否与肥胖、高血压或糖尿病成人参与者的炎症标记物(CRP、纤维蛋白原、WBC)水平有关；2：在30名瘦肉和30名肥胖的成年高血压志愿者中进行的临床试验中，确定3周的天然高纤维饮食(30g/天)或通过补充高纤维饮食是否会显著减少炎症标志物；3：对180名肥胖的成年志愿者进行了为期三个月的临床试验，以确定与通常的低纤维饮食(平均每天10-15g)相比，补充中等纤维(额外7g/天)或高纤维(15g/天)的饮食是否会显著降低炎症标志物。 为了达到这些目标，我们计划进行三项相关研究。第一个将利用国家健康和营养检查调查中包含的现有数据，这是一个由5773名非制度化成年人组成的国家数据库。第二项研究将是其中一名研究人员在现有R01基础上进行的额外程序和实验室检查，以检查天然高纤维饮食对CRP和其他炎症标志物的影响。第三项研究将包括对180名志愿者的新的初步数据收集，以评估不同水平的纤维补充对CRP、纤维蛋白原、白细胞和白细胞介素6的影响。通过使用现有的数据，利用正在进行的方案，并通过初级数据收集添加新的信息，我们希望极大地增加我们对膳食纤维和心血管炎症标志物之间的关联的理解。这些信息可能有助于指导营养指南的建设性变化，以降低数百万高危人群的心血管疾病风险。

DESCRIPTION (provided by applicant): The purpose of this research is to investigate the relationship between dietary fiber and cardiovascular inflammatory markers. Recent studies have found that diets with higher fiber intake are associated with a reduction in cardiovascular disease (CVD). However, the association does not prove that dietary fiber is actually responsible for lower CVD risk nor does it illuminate potential mechanisms of lower risk if present. Since the diet-CVD connection is strong, and given that CVD is a major contributor to morbidity and mortality, additional information would be valuable. Our preliminary studies and the work of others suggest that there is a significant association between C-reactive protein (CRP) and dietary fiber intake. These observations led us to the following unifying hypothesis: Diets high in fiber are associated with lower levels of inflammatory markers. Our long-term goal is to determine whether inflammation is a key mediator in the link between fiber intake and cardiovascular disease risk. The three specific aims of the project are 1: To determine whether total dietary fiber and or fiber supplementation is associated with levels of inflammatory markers (CRP, fibrinogen, WBC) among adult participants with obesity, hypertension, or diabetes in the National Health and Nutrition Examination Survey 1999-2000; 2: To determine whether 3 weeks on a diet naturally high in fiber (30g/day), or on a diet high in fiber through supplementation, will significantly reduce inflammatory markers compared to a diet low in fiber, in a clinical trial among 30 lean and 30 obese adult hypertensive volunteers; and 3: To determine whether 3 months on a diet supplemented with moderate fiber (extra 7g/day), or high fiber (15g/day), will significantly reduce inflammatory markers compared to a usual diet low in fiber (average 10-15g/day) in a three-month long clinical trial among 180 obese adult volunteers. To accomplish these aims, we plan to conduct three related studies. The first will utilize existing data contained in the National Health and Nutrition Examination Survey, a national database of 5773 non-institutionalized adults. The second study will be an additional procedure and laboratory examination to an existing R01 by one of the investigators, to examine the impact of a diet naturally high in fiber on CRP and other inflammatory markers. The third study will consist of new primary data collection in 180 volunteers to evaluate the effect of different levels of fiber supplementation on CRP, fibrinogen, WBC, and interleukin-6. By using existing data, taking advantage of an ongoing protocol, and adding new information through primary data collection, we hope to dramatically increase our understanding of the association between dietary fiber and cardiovascular inflammatory markers. This information could serve to guide constructive changes in nutritional guidelines for reducing CVD risk for millions of at-risk individuals.