Date of Award

8-2006

Level of Access

Campus-Only Thesis

Degree Name

Master of Science (MS)

Department

Food Science and Human Nutrition

Advisor

Mary Ellen Camire

Second Committee Member

Alfred Bushway

Third Committee Member

Richard A. Cook

Abstract

Cardiovascular disease (CVD) is the number one killer in the United States of all races, all ages, and both sexes and results in over 927,000 American deaths every year. In the state of Maine, heart disease is the leading cause of death followed by cancer and stroke. The cost of CVD exceeds $390 billion every year. High blood cholesterol is an independent risk factor of CVD and is related to the development of atherosclerosis due to the oxidation of blood lipids. Blueberries contain high levels of antioxidants including anthocyanins that have been shown to reduce free radicals in the body. It is hypothesized that the free radical absorbance and antioxidant ability of the anthocyanins in blueberries may result in beneficial alterations in blood lipids when consumed as a part of a heart- healthy diet. Twenty-six adults with elevated low-density lipoprotein (LDL) cholesterol greater than 3.4 mmol/L (130 mg/dL) and less than 4.9 mmol/L (189 mg/dL) were recruited for this randomized control study. Weight, blood pressure, and fasting blood analyses were obtained at weeks 0, 4, and 8 of intervention. Blood analyses included cholesterol (total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein, and triglycerides), high sensitivity C - reactive protein, and total antioxidant status. Subjects were randomly assigned to a control or blueberry group; nine control subjects and 17 blueberry subjects completed the study Both groups were asked to follow the National Heart, Lung, and Blood Association's (NHLB) Therapeutic Lifestyle Changes (TLC) Diet personalized by subject gender, age, Body Mass Index, and activity level. The blueberry group was also asked to consume two half-cup servings (~64 grams each) per day of frozen blueberries provided by the Wild Blueberry Commission of North America. Three-day food records were collected at 4 and 8 weeks to estimate compliance. No significant differences between groups were observed for serum total cholesterol, LDL cholesterol, total antioxidant status or blood pressure. Significant difference resulted for serum triglycerides, HDL cholesterol, and total cholesterol to HDL ratio. High-sensitivity C-reactive protein levels were inconsistent, suggesting that infection or other inflammatory factors confounded treatment effects. A few subjects lost weight during the study but most did not illustrate a weight change. Compliance with the TLC diet was poor and contributed to limited improvement in CVD markers. Beneficial alterations in blood lipids were observed in some subjects consuming blueberries but future research is needed to understand the potential for disease prevention by blueberries.

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