See also: Sweet Potato Facts & Trivia
Recipes for Yams & Sweet Potatoes
True yams may have been cultivated as early as 8,000 B.C. in Asia.
What are frequently called yams, especially in the Southern U.S., are in fact sweet potatoes. The two are not related, even though they look similar and are used in pretty much the same way.
Despite a physical similarity and a frequent confusion with their names, yams and sweet potatoes are not even distantly related. They are in two different botanical families. Yams are actually related to grasses and lillies.
Estrogens (sex hormones) were first made from a similar compound in yams. Yams were used commercially to produce hormones for contraceptive pills, and steroids.
At one time, growing yams to be used in drug production (steroids, oral contraceptives, sex hormones) was a major industry in Mexico, providing 80% of the raw material for production of steroidal drugs.
The water yam commonly cultivated in Southeast Asia, grows up to 8 feet long and can weigh over 100 pounds.
One species of yam is used to make a dye in southern China.
Many wild species of yam contain the poisonous dioscorines, but when peeled and boiled or roasted they are said to be safe to eat. There are about 600 species of yam, 150 of which are cultivated for food.
Yams can grow to huge sizes, and on the Pacific Island of Ponape, yams are referred to as 2 man, 4 man, or 6 man yams, depending on how many men it takes to lift the tuber. Some have been accurately recorded up to 600 pounds and 6 feet in length
The annual world production of yams is over 30 million tons.
The yamaimo root or mountain yam, is a Japanese variety of yam, once reserved only for the Japanese nobility.