generally, continue to expand rapidly, prebiotics, probiotics, their characteristics and health benefits become a more and more interesting field for scientific research. Their primary features and their impact on human health will be discussed in this essay. Prebiotics-definition and sources According to Gibson and Roberfroid (1995) prebiotics are “nondigestible food ingredients that beneficially affect the host by selectively stimulating the growth and/or activity of one or a limited number of bacteria