The rhubarb, a tart, earthy vegetable commonly used in pies, originated in the cold climates of Western China, Tibet, Mongolia and Siberia. This vegetable played a medicinal role for centuries before it began to be consumed as food in the 18th century. While rhubarb stalks are safe to eat, rhubarb leaves can cause poisoning if consumed raw or cooked.
Toxic Substances
Rhubarb leaves contain the poisonous toxin oxalic acid, a substance also found in anti-rust products, metal cleaners and bleaches. Consumption of large amounts of oxalic acid can cause potentially fatal poisoning. Anthraquinone glycosides in rhubarb leaves also may be toxic, according to MedlinePlus Medical Encyclopedia. Unlike rhubarb leaves, rhubarb stalks do not contain significant amounts of any toxin.
Symptoms of Poisoning
Poisoning symptoms from rhubarb leaves include burning in the mouth or throat, difficulty breathing, eye pain, stomach pain, nausea and vomiting, weakness, diarrhea, kidney stones or red-colored urine. In severe cases, rhubarb leaf poisoning may cause seizures, coma and kidney failure. Deaths from rhubarb leaves poisoning have been reported only rarely, notes MedlinePlus Medical Encyclopedia.
Treatment
Contact a poison control center and get medical help right away if you suspect someone is suffering from rhubarb leaves poisoning. Try to determine how large a quantity of rhubarb leaves the person consumed and at what time, and give this information to the health care provider. The doctor also may need to know the person's age, weight and health history. Treatment may include gastric lavage, breathing support, intravenous fluids and activated charcoal.
Edible Rhubarb
Rhubarb stalks are edible, though they are typically too sour to eat without added sugar, fruit juice or honey, notes the Centers for Disease Control and Prevention. Like most vegetables, rhubarb stalks are low in calories and fat. A 1/2-cup serving of diced rhubarb stalks contains 15 calories, 3 g of carbohydrates, 1 g of sugar and no fat, cholesterol or sodium. This serving also provides 1 g of dietary fiber, 1 g of protein, 8 percent of the recommended daily vitamin C intake, 6 percent of the recommended daily calcium intake and 2 percent of the recommended daily vitamin A intake.
