Probiotics (“for life”) is a live microbial feed supplement or defined as mono- or mixed cultures of live microorganisms which when administered in adequate amounts confer  a health benefit to the host by improving its microbial balance. Common descriptives for probiotics include “friendly”, “beneficial” or “healthy” bacteria.  Under natural conditions a protective gut microflora develops and there is no  need for probiotics supplement, but under rather un-natural conditions such like intestinal infections, post antibiotic treatment syndromes, pseudomembranous colitis, the probiotics preparations are needed. The beneficial effects of probiotics inthe host are promotion of the gut maturation and integrity, antagonisms against pathogens and immune modulation. Beyond those, the microflora seems to play a significant rolein diet induced superinflammation, mucosal immune system, neuroendocrine regulation, immunoglobulin production, macrophages factor restoration, apoptosis stimulation, lymphocyte function modulation, cytokine release, mucin production, intestinal immune homeostasis and inflammation prevention. However, many studies proved that probiotics have “upregulation and down-regulation” effects on immune system of the host.