Metabolic Response to Chardonnay Grape Marc Powder

Previous research on grape seed nutritional properties has predominantly been confined to grape seed extracts (GSE) containing only soluble components. In animal models, GSE has been shown to prevent increases in blood pressure, blood cholesterol, and insulin resistance. In humans, there have been improvements in blood pressure, however no significant effect on blood cholesterol levels. Whole milled grape marc flours deliver more dietary complexity than seed extracts alone. In addition to the extractable and non-extractable polyphenols, flour offers dietary fiber, minerals, sterols and polyunsaturated fats. Grape marc flour is currently used as a food ingredient that is incorporated into various baked goods. However, to obtain good control of the dose level, the product will be provided in capsule form for this study. For reference, a ½ cup of of a high polyphenol food such as blueberries, contains about 325 milligrams of polyphenols, thus even with the higher dose, participants will be receiving an amount of polyphenols that is less than ¼ cup of blueberries. The grape marc powder is prepared in a facility that is certified for producing food-grade products, and the nutritional composition and safety of the product will be thoroughly evaluated before we begin the study. The objective of the current study is to determine if this chardonnay grape marc powder enriched with grape seed extract supplementation has beneficial impacts on the human blood lipid profile and to correlate gut biome changes to human metabolism.

Inclusion criteria

• BMI ≥ 25 and < 40 kg/m2
• Dyslipidemia as defined as (any one or all of the following values):
• Total cholesterol > 190 mg/dL but < 240 mg/dL
• LDL-cholesterol > 130 mg/dL but < 160 mg/dL
• HDL-cholesterol < 40 mg/dL (men)/<50 mg/dL (women)
• Fasting triglycerides > 150 mg/dL but < 300 mg/dL

Exclusion criteria

• Renal, cardiovascular, gastrointestinal or hepatic disease, by medical history
• History of a previous cardiovascular event
• Diagnosis of type 2 diabetes
• Pregnancy or lactation
• Use of tobacco
• Food sensitivities or allergies to the foods or components of foods provided in the standard meals including gluten, dairy, egg, soy, nuts, or seafood
• Use of herbal or plant-based supplements; omega-3 fatty acids, and fish oils in the past 3-6 months, and unwilling to discontinue use while participating in the study.
• Use of lipid-lowering, glucose-lowering, anti-hypertensive, or weight loss medications
• Use of antibiotics in the last three months.