Vanilla is a member of the vast orchid family, it grows as a tall creeping vine on trees or frames. Native to South and Central America and the Caribbean, the first people to have cultivated vanilla are thought to have been the Totonacs on Mexico's east coast. The Aztecs acquired vanilla when they conquered the Totonacs in the 15th Century; the Spanish then brought it to Europe and North America when they conquered the Aztecs. Vanilla is the world's second most expensive spice because it is so labour intensive to harvest.
Each flower (see image) remains open for only 24 hours before they wilt and die. When the French first transported vanilla to Reunion island they found that the plants were sterile and wouldn't bear fruit because no insects pollinated them. A botany professor developed a method of manual pollinisation, however Edmond Albius, a 12 year old slave, managed to pollinate the plants using just a thin stick or leaf and a careful hand action. This method is still used today and is the primary reason why farmers around the world have been able to make vanilla a profitable crop. Today roughly 75% of the world's vanilla comes from Madagascar and Reunion.
Synthetic vanillin is much cheaper to produce (either by using yeast, algae or chemical processing) and so this is far more commonly used in food products. However vanilla contains hundreds of chemicals that contribute to its unique taste and smell and vanillin only makes up 2% of the vanilla bean. Traditional medicinal uses of vanilla include treatment for fever, dysmenorrhea (menstrual pain),muscle spasms, blood clotting, and gastrointestinal problems. Modern research on the biological actions of vanilla is very limited however some studies have suggested beneficial effects on the heart, reducing cholesterol and risk for heart attacks and strokes. Vanilla is also an antioxidant and antibacterial. The scent alone is said to reduce anxiety and stress, I know that works for me when I smell freshly baked cookies.