Probiotic foods and supplements continue to gain in popularity and flourish with a worldwide market worth around US $6 billion annually. "Probiotics", by the generally accepted definition, are "live microorganisms which when administered in adequate amounts confer a health benefit on the host". The human intestine is colonized by a large number of microorganisms that inhabit the intestinal tract and support a variety of physiological functions. The stepwise microbial colonization of the intestine begins at birth and continues during the early phases of life to form an intestinal microbiota that is different for each individual, depending mainly upon the environment and food habits. This process facilitates the formation of a physical and immunological barrier between the host and the environment and thus, helping the gastrointestinal tract maintain a disease-free state.
展开▼
