Capsaicinoids are molecules derived from chili peppers. They are best known for their pungency, producing mild to intense spice upon ingestion. It has long been known that peppers possess unusual qualities. Historically, they were burned in war rituals, and used to stimulate appetite. In 1997, a gene that encoded for a receptor specific for capsaicinoids was identified. Called VR1, this fatty acid receptor is present only on C fibers, and when activated produces desensitization or degeneration of the sensory afferent. Today, capsaicinoids are being studied as effective treatments for a number of sensory nerve fiber disorders, including pain associated with arthritis, cystitis, human immunodeficiency virus, and diabetic neuropathy.