Dietary Fiber and Cardiovascular Inflammatory Markers

描述（由申请人提供）：本研究旨在探讨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，也没有阐明如果存在降低风险的潜在机制。由于饮食与心血管疾病的联系很强，并且心血管疾病是发病率和死亡率的主要因素，因此额外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）与膳食纤维摄入量之间存在显著关联。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有关。我们的长期目标是确定炎症是否是纤维摄入与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 .确定1999-2000年全国健康与营养调查中肥胖、高血压或糖尿病成年参与者的总膳食纤维和/或纤维补充是否与炎症标志物（CRP、纤维蛋白原、白细胞计数）水平相关；2：在30名瘦和30名肥胖成年高血压志愿者的临床试验中，确定3周的高纤维饮食（30克/天），或通过补充高纤维饮食，是否会比低纤维饮食显著减少炎症标志物；3：在180名肥胖成年志愿者为期3个月的临床试验中，确定3个月的膳食补充适度纤维（额外7克/天）或高纤维（15克/天）是否会显著减少炎症标志物，而不是通常的低纤维饮食（平均10-15克/天）。

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.