Fermented food, such as tempeh in Indonesia and Natto in Japan, have been shown to alter gut microbiota in animal experimentation. Owing to their biological activities, these fermented food can alter the composition of gut microbiota in animal and possibly in human as well. Alternation has been linked to development of chronic diseases. It would be important to understand if indeed such an effect on the species of microbiota will have a direct effect on the development if chronic diseases.