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ARS Home » Pacific West Area » Davis, California » Western Human Nutrition Research Center » Obesity and Metabolism Research » Research » Research Project #430521

Research Project: Grape Seed Flour Manufacture and Study of Human Metabolic Response

Location: Obesity and Metabolism Research

Project Number: 2032-51530-025-002-T
Project Type: Trust Fund Cooperative Agreement

Start Date: Apr 1, 2016
End Date: Sep 30, 2019

Objective 1: Evaluate the contribution of non-extractable polyphenols to changes in blood lipid profiles and healthful changes (specifically, weight gain or loss, plasma lipoprotein cholesterol and triglycerides) in healthy, mature adults after consumption of food products containing chardonnay grape seed flour (CGSF) at low (3 g/day) and a high amounts (10 g/day) for 4 weeks. Concurrently, participants will be surveyed for satiety and cognition; measurements of bacterial metabolites in breath and altered bile acid content in feces and blood. Objective 2: Determine if consumption of CGSF alters the fecal microbiome and fermentation products originating in the lower gut.

A randomized controlled trial (RCT) using a cross-over design will be conducted with 24 mature adults who present with risk factors for cardiovascular disease. Three intervention treatments (duration: 4 weeks) will be tested in counter-balanced order: placebo-control, low and high dose of CGSF incorporated into food and beverage products that will be ingested along with participants’ usual diets. The first intervention period will be preceded by a run-in period to collect baseline samples, and subsequent intervention periods will be separated by 4-week wash-out periods. Experimental testing/data collection will be done at baseline and at the end of each 4-week intervention period. Protocols will include measurements of fasting and postprandial blood lipid and bile acid profiles, glycemia, insulinemia, incretin hormones, and breath hydrogen and methane production (a standard test meal will be provided with corresponding CGSF level to examine postprandial responses); anthropometric and body composition measurements; measure of vascular function (peripheral vascular tone); assessment of cognitive function; analysis of fecal microbiota, volatile fatty acids, and bile acids.