Hoodia is derived from a southern African plant and is thought to suppress hunger. Native hunters reportedly use this plant during long hunts to allay hunger. However, they do not necessarily use it daily, and the use of this plant daily is unknown. There have been no placebo-controlled studies to determine whether it is effective or safe when taken daily. What has been determined is that some supplements promoted as containing hoodia have been found to actually not contain any, or in such a small quantity as to be negligible.