Grape fruit extracts are used for preventing diseases of the heart and blood vessels(5), varicose veins, hemorrhoids, atherosclerosis(7), (8), high blood pressure, swelling after injury or surgery, heart attack, and stroke. Fruit extracts contains flavonoids, which can have antioxidant effects, lower the levels of LDLs (“bad cholesterol”)(8), relax blood vessels, and reduce the risk of coronary heart disease. Red grape varieties provide more antioxidants than white or blush grape varieties(1).
One study found white grape juice extract exerted both bacteriostatic and bactericidal activity in vitro. It inhibited Staphylococcus aureus and E. coli, though demonstrated no effect on the growth of Candida sp. and the fungus Aspergillus niger(2). Another study found growth of all tested antibiotic-resistant bacterial and mold species, except S. typhimurium and E. coli, to be significantly inhibited by all the solvent extracts of black grape peel(3).
Another compound found in grape skin is resveratrol, a polyphenol thought to act like antioxidants and protecting the body against damage that increases risk for things like cancer and heart disease. Resveratrol is thought to help reduce inflammation, lower LDL (“bad” cholesterol), and make it more difficult for clots to form that can lead to a heart attack(5). It may protect nerve cells from damage and fight plaque buildup that can lead to Alzheimer’s(4), (6). It helps prevent insulin resistance, which can lead to diabetes.
1)WebMD. Find a Vitamin or Supplement: GRAPE. 2005-2016. http://www.webmd.com/vitamins-supplements/ingredientmono-472-GRAPE.aspx?activeIngredientId=472&activeIngredientName=GRAPE&source=2
5)WebMD. Heart disease: Resveratrol supplements. 2005-2016. http://www.webmd.com/heart-disease/resveratrol-supplements
2)Filocamo A, Bisignano C, Mandalari G, Navarra M. In vitro antimicrobial activity and effect on biofilm production of a white grape juice (Vitis vinifera) extract. Evidence-Based Complementary and Alternative Medicine. 2015 Dec 7;2015. http://downloads.hindawi.com/journals/ecam/2015/856243.pdf
3)Yadav D, Kumar A, Kumar P, Mishra D. Antimicrobial properties of black grape (Vitis vinifera L.) peel extracts against antibiotic-resistant pathogenic bacteria and toxin producing molds. Indian journal of pharmacology. 2015 Nov;47(6):663. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4689022/
4)Porquet D, Casadesús G, Bayod S, Vicente A, Canudas AM, Vilaplana J, Pelegrí C, Sanfeliu C, Camins A, Pallàs M, Del Valle J. Dietary resveratrol prevents Alzheimer’s markers and increases life span in SAMP8. Age. 2013 Oct 1;35(5):1851-65. http://digital.csic.es/bitstream/10261/89182/3/Dietary%20resveratrol.pdf
6)Pasinetti GM, Wang J, Ho L, Zhao W, Dubner L. Roles of resveratrol and other grape-derived polyphenols in Alzheimer's disease prevention and treatment. Biochimica et Biophysica Acta (BBA)-Molecular Basis of Disease. 2015 Jun 30;1852(6):1202-8. http://www.sciencedirect.com/science/article/pii/S0925443914003123
7)Agarwal B, Campen MJ, Channell MM, Wherry SJ, Varamini B, Davis JG, Baur JA, Smoliga JM. Resveratrol for primary prevention of atherosclerosis: clinical trial evidence for improved gene expression in vascular endothelium. International journal of cardiology. 2013 Jun 5;166(1):246. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3646959/
8)Chang GR, Chen PL, Hou PH, Mao FC. Resveratrol protects against diet-induced atherosclerosis by reducing low-density lipoprotein cholesterol and inhibiting inflammation in apolipoprotein E-deficient mice. Iranian journal of basic medical sciences. 2015 Nov;18(11):1063. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4764106/
Singh N, Agrawal M, Doré S. Neuroprotective properties and mechanisms of resveratrol in in vitro and in vivo experimental cerebral stroke models. ACS chemical neuroscience. 2013 Jun 24;4(8):1151-62. https://www.researchgate.net/profile/Megha_Agrawal5/publication/237198661_Neuroprotective_Properties_and_Mechanisms_of_Resveratrol_in_in_Vitro_and_in_Vivo_Experimental_Cerebral_Stroke_Models/links/00b4951d1ad90b2ad4000000.pdf