- Contains vitamin C, potassium, and fiber.
- Ususally prepared with substantial amount of sugar or other sweeteners
- Contains oxalic acid, which inhibits calcium
- Leaves are highly poisonous
Although rhubarb is generally regarded as a fruit, botanically it is a vegetable. It is available in frozen and canned forms, but most people prefer to cook the fresh stalks themselves. One cup of fresh diced rhubarb yields an mere 26 calories and provides 10 mg of vitamin C, as well as 350 mg of potassium. This same serving size also contains more than 100 mg of calcium; however, rhubarb is not considered a good source of this mineral, since is aslo contains oxalic acid, which not only blocks the absorption of its calcium, but also that form any other dietary sources. Because it has a high oxalic acid content, large amounts of rhubarb should be avoided by anyaone with a tendency to develop oxalate-containing kidney or gall stones..