The Kalahari Bushmen for tens of thousands of years considered the Hoodia plant not only as an appetite suppressant but also as food, water, and a source of energy. This sparked the curiosity of the South African Government’s Council for Scientific and Industrial Research (CSIR), especially after a Dutch ethno-biologist produced a research paper about its uses in 1937. So how does Hoodia work in curbing appetite? To explain in layman’s terms, when Hoodia is taken its active ingredient imitates the effects of glucose sugar on the brain’s nerve cells. They tell the brain that the body is full and doesn't need any more food, causing the brain to diminish appetite.