Only a glass of purple grape juice in a day could leave you from heart disease and also from cancer. Purple grape juice having the highest level of polyphenols which helps in keeps away from heart disease and also from cancer. It is one of the effecting from of all juices. You already know that fruits contain antioxidants called polyphenols that helps to neutralize unbalanced oxygen molecules called free radicals. So just drink one glass of purple grape juice and leave healthy.