Table 2.

Clinical trials to assess the effect of grape powder in different diseases

Grape formulation and dosages	Model/disease condition	Outcome of the study	References
Grape powder (80 or 120 g/day) or resveratrol (20 or 80 mg/day) for 14 days	Colon cancer (N = 8)	Grape powder inhibited the expression of a panel of Wnt target genes in normal colonic mucosa.	42
Grape powder (74.2 g) was given on two occasions separated by 2 weeks	Oxidative stress (N = 8)	Consumption of grape powder with meal was found to increase the levels of hydrophilic antioxidant capacity.	43
Grape powder (500 mg of polyphenols/day) or placebo for 5 weeks.	Inflammatory and antioxidant markers in HD patients (N = 16)	Grape powder consumption increased the activity of GSH-Px and reduced the inflammation progression in hemodialysis (HD) patients.	44
Muscadine grape seed (1300 mg or placebo) daily for 4 weeks, with a 4 week washout.	Subjects with coronary disease or ≥ 1 cardiac risk factor (N = 50)	Muscadine grape seed supplementation increased baseline diameter (mm) without improved flow-mediated dilatation (FMD).	45
Red grape cell powder (RGC) (200 or 400 mg or placebo) daily for 12 weeks.	Subjects with prehypertension and mild hypertension (N = 50)	RGC consumption was associated with an improvement of FMD (indicating endothelial function), decrease in lipid peroxidation and diastolic blood pressure without any adverse effects.	46
Grape powder (46 g) or placebo two time a day for 3 weeks	Obese subjects with BMI = 30–45 kg/m2) (N = 24)	Grape powder increased IL-1β and IL-6 production, and reduced plasma concentrations of large LDL and large LDL- cholesterol particles in obese humans.	47
Grape powder (46 g/day) for 4 weeks	Men with metabolic syndrome (N = 24)	Grape consumption displayed anti-oxidative markers and increased anti-inflammatory markers in the absence of the inflammatory milieu associated with dyslipidemias.	48
Grape powder (46 g/day) for 30 days	Men with metabolic syndrome (N = 24)	Grape supplementation improved vascular endothelial function and biomarkers of metabolic syndrome by increasing FMD, and decreasing systolic blood pressure and circulating inflammatory molecules.	49
Grape powder (36 g) or a placebo for 4 weeks	24 pre- and 20 postmenopausal women	Grape supplementation demonstrated a cardioprotective effect in pre- and postmenopausal women by lowering oxidative stress and plasma lipid levels.	50
Grape powder (94 g/day) for 6 weeks	Postmenopausal women (N = 18)	No significant changes were noticed in plasma hormone levels.	51