Rhubarb: Its history and uses

07/06/2017

The Chinese had been using rhubarb as a medicinal plant for thousands of years before its introduction to Europe. Rhubarb was considered valuable because of its laxative properties, and its root was considered to have anti-cancer properties. Here I will discuss the properties of the stems; the root is not used in the West and little has been published about its safety.

Beginning in the seventh or eighth century, rhubarb was imported into Europe along the Silk Road. Later it started arriving through maritime routes or overland through Russia. In medieval Europe it was expensive—more so than cinnamon, opium and saffron. Nevertheless, it was popular because of its laxative and purgative properties. Apothecaries in medieval times preferred the plants that came from Russia, known as Siberian rhubarb.  

In the United States, medicinal and culinary rhubarb was grown in the early 1700s. Thomas Jefferson planted it at Monticello and is quoted as saying that the leaves are as excellent as spinach. But in this he was greatly mistaken: rhubarb leaves are extremely toxic and high in oxalic acid, and should never be eaten or given to animals. Put them in your compost. (I hope Jefferson did not encourage his slaves to eat them.) People who have had urinary stones containing oxalic acid, or calcium oxalate stones, should drink lots of water and avoid too much food high in oxalate. That includes rhubarb, beets, okra, spinach, Swiss chard, nuts, tea and chocolate. 

On the positive side, rhubarb is high in vitamin K, which supports healthy bone growth and brain function. It contains lutein, which is beneficial for the eyes, as well as calcium and many other vitamins and minerals. Researchers are interested in substances in rhubarb that kill human leukemia cells and slow the growth of lung cancer cells in mouse models.  

Rhubarb is sour, so cooks need to add sweetening to make it palatable for most people. You can cook it with raisins and cinnamon and add a bit of sugar or honey at the end to taste. There are some good recipes on the Web for rhubarb chutney. 

 

Sadja Greenwood, a Bolinas resident, is a retired physician formerly active at the University of California, San Francisco. Read more of her work at sadja.blogspot.com.