The sour leaves of sorrel and sheep sorrel have long been appreciated for their tart flavour, which provided a good source of vitamin C in the days when citrus fruit where not so readily available. They have often been included in spring cleansing diets and in France and Germany they have a solid place in traditional wild herb soups. Yet, gardeners are usually not very pleased to encounter this herb in their gardens and consider it a weed. Children, on the other hand, like its sour taste and often munch on the leaves. However, the tart flavour is due to a high amount of oxalates, which are sharp little crystals that can be damaging to the kidneys if eaten in large quantities. Oxalates are also commonly found in spinach and rhubarb.
Sheep's sorrel has cleansing properties, stimulates cellular regeneration and acts as a cooling astringent. It is often given as a cooling febrifuge tea. Its cleansing properties can purify the blood and help to eliminate toxins. Sheep Sorrel is thought to be one of the most active ingredients of Essiac, the famous anti-cancer remedy of the Canadian nurse Rene Caisse. Sheep's Sorrel is rich in phytoestrogens, which are usually more commonly associated with the Clover family, and also has a strong anti-oxidant effect. It is said to be a reliable vermifuge. It can be used as a supportive remedy in certain skin conditions. In low doses it can reduce excessive menstrual bleeding and diarrhoea.
Sheep's Sorrel can be used as incense to protect the cattle against disease and worms. It is also said to ward off lice.