Potatoes juice.

Another interesting information.

Phytochemicals & Antioxidants in Potato Juice. http://www.thejuicenut.com/potato_juice_the_juice_nut.aspx

During World War I, a group of German soldiers, near starvation, were forced to live on raw potatoes. The soldiers with gastric disorders were relieved and cured. After the war, Dr. J. F. Magerl began treating gastric patients with raw potato juice. After ten days of the treatment, most of the patients showed no symptoms. Potatoes can come in a multitude of colors, including orange, red, or yellow, and even purple and blue. And as with all veggies, the richer the pigments, the higher the phytochemical punch. For example, there is a red and purple fleshed potato that contains high levels of anthocyanins, which have been shown to inhibit human tumor cells. Dark yellow or orange spuds are high in the carotenoid zeaxanthin, which can fight certain eye diseases.