Sheep sorrel provides a number of vitamins and minerals. These include about 60 milligrams of vitamin C in 1 cup of chopped leaves and over 5,000 international units of vitamin A, plus small amounts of several B vitamins in the same-size serving. The herb also contains calcium, with about 60 milligrams per cup, and more than 500 milligrams of potassium, along with some magnesium, phosphorus and a small amount of zinc. In addition, sheep sorrel contains a number of natural phytochemicals, including several flavonoids such as quercetin, which have antioxidant properties. It also provides other compounds called anthraquinones, additional antioxidants that can benefit your digestive tract.