From the large growing rhubarb only the often red coloured, fleshy leaf stalks are eaten. They are peeled, cut into pieces and processed into compote, jam and cake filling, as well as juice and most. The stems are hardly sweet and are therefore usually given sugar. Leaves and stems contain (besides vitamins, minerals and fruit acids) a lot of oxalic acid, which deprives the body of calcium and causes strain on the kidneys. For this reason, rhubarb should not be eaten in excessive quantities and should be avoided by people with kidney problems.