Rhubarb has been used in traditional Chinese and Tibetan medicine for more than 5,000 years, and it gradually spread to India, Russia, Europe and eventually North America. Rhubarb belongs to the same family as buckwheat and sorrel. It produces huge leaves on reddish celery-like stalks. These stalks have a distinctly tart taste, but when sweetened with sugar they make a popular food.
Both the stalks and the root of the plant are used to make medicines. The leaves, however, contain highly toxic oxalic acid and should never be consumed.
Herbalists have traditionally used rhubarb as a laxative, diuretic, and to treat kidney stones, gout, and liver diseases. It is also used externally to heal skin sores and scabs. In traditional Chinese medicine, rhubarb is used as an ulcer remedy and to “clear heat” from the liver, stomach and blood. It is also used for de-worming, fever, toothaches and headache.
“Swedish bitters” is a popular tonic, especially in Europe, and it includes rhubarb as one of its active ingredients, along with aloe and senna. But frequent use of this tonic is not recommended due to the risk of bowel dependence.
Recent research has identified several active compounds in rhubarb that may act to fight cancer, reduce inflammation and lower cholesterol, as well as protect the eyes and brain. These compounds are strong antioxidants called anthraquinones. One of these, called emodin, is found in high concentrations in rhubarb, and promising new research suggests it might inhibit cell proliferation, induce cell death in cancer cells and prevent cancer from spreading.
Rhubarb also contains anthocyanins (the type of pigment also found in blueberries), lutein and zeaxanthin, as well as significant amounts of vitamins (C, K, B-complex) and the essential minerals calcium, potassium, and manganese.