The mammalian intestinal microbiota comprises many different species of bacteria, viruses, fungi, yeasts, and bacteriophages. This community starts to develop at birth and continues for 3–5 years, in humans, until it reaches a stable composition [1]. However, it continues to be influenced by different environmental and lifestyle factors during lifetime. Under healthy conditions, the microbiota influences numerous physiological processes within the host, such as protection against pathogens, nutrient digestion and absorption, development, and education of multiple host organs and the immune system.