Nutrition 2008 Jul-Aug;24(7-8):646-53. Epub 2008 May 15.
Department of Metabolism and Nutrition, Consejo Superior de Investigaciones Científicas, Universidad Complutense de Madrid, Madrid, Spain.
Objective: The objective of the study was to evaluate the effects of a grape product rich in dietary fiber and natural antioxidants on cardiovascular disease risk factors.
Methods: A randomized, controlled parallel-group trial was carried out. Thirty-four non-smoking (21 normocholesterolemic and 13 hypercholesterolemic) adults were supplemented for 16 wk with 7.5 g/d of grape antioxidant dietary fiber, a natural product containing 5.25 g of dietary fiber and 1400 mg of polyphenols. Nine non-supplemented non-smokers were followed as a control group. Fasting blood samples, blood pressure, and anthropometric readings were obtained at baseline and at week 16. Subjects were allowed to consume their regular diet, which was monitored weekly.
Results: Grape antioxidant dietary fiber (7.5 g/d) reduced significantly (P < 0.05) total cholesterol (9%), low-density lipoprotein cholesterol (9%), and systolic and diastolic blood pressures (6% and 5% respectively). Greater reductions in total cholesterol (14.2%) and low-density lipoprotein cholesterol (11.6%, P < 0.05) were observed in hypercholesterolemic subjects. No changes were observed in the control group. There was a reduction of 2.5 points in the Framingham Global Risk Score in the supplemented group. A significant reduction in triacylglycerol concentration took place in the supplemented hypercholesterolemic subjects (18.6%, P < 0.05).
Conclusion: Grape antioxidant dietary fiber showed significant reducing effects in lipid profile and blood pressure. The effects appear to be higher than the ones caused by other dietary fibers, such as oat fiber or psyllium, probably due to the combined effect of dietary fiber and antioxidants.