The Benefits of Good Bacteria Lactobacilli and Bifidobacteria are the friendly bacteria that normally occur in the human gastrointestinal and genitourinary tracts and play important roles in promoting good health.  They re-colonize areas of the body where friendly bacteria may be depleted for one reason or another.  This is important since the body relies on these probiotics for several functions including the absorption of nutrients, preventing colonization by pathogenic (harmful) bacteria, and metabolizing foods and certain drugs. A Probiotic Deficiency Since probiotics are not nutrients, they are often not considered to be something that one can be deficient in.  Nevertheless, some inflammatory conditions of the gut are thought to be caused, at least in part, by a deficiency of bifidobacteria. Furthermore, there is a range of adverse ramifications that can surface when probiotics are not present in adequate quantities. A sufficient supply of friendly, probiotic organisms are necessary to inhibit the spread of the harmful, pathogenic organisms that can often result in symptoms of periodic diarrhea, heartburn, indigestion, lactose intolerance, food sensitivities, a weakened immune system, fatigue, low energy, fungal infections, yeast infections, etc. Clinical use of Probiotics In addition to the prevention and treatment of probiotic deficiency, probiotics have also been advocated for the prevention and treatment of a wide range of disorders, and there is strong evidence for their efficacy in some clinical scenarios. In fact, probiotics are now widely used in many countries by consumers and in clinical practice. A significant amount of research has been conducted regarding the different probiotic strains, and the value that these individual strains have for human health.  The following is a brief review of that research. The Lactobacillus species Lactobacillus refers to a group of lactic acid producing, friendly bacteria that make up many of the 400 normal probiotic species in the human body. Lactobacilli provide many benefits, including the following:

• Inducing growth factors and increasing the bioavailability of minerals.
• Stabilizing the mucosal barrier and decreasing intestinal permeability.
• Reducing undesirable bacteria by producing lactic acid and hydrogen peroxide.
• Immunomodulating effects such as promoting healthy immune function.
• Promoting healthy levels of Candida albicans.

The Bifidobacterium species Bifidobacteria normally colonize in the human colon and, like Lactobacillus species, also produce lactic acid. These probiotics are important organisms in the intestine in helping to create a microbial barrier to undesirable bacteria.  In fact, some species of Bifidobacteria (including B. infantis, B. breve and B. longum) bind to the intestinal mucosa and interfere with the attachment of undesirable bacteria. Since Bifidobacteria disappear from the feces within 2 weeks after discontinuing supplementation, this suggests that there is no long-term colonization  so Bifidobacteria must be used regularly to achieve a continued benefit. Pediococcus acidilactici Although Pediococcus acidilactici is not a natural component of the microintestinal flora, it is safe (belongs to the GRAS list) and has been well studied in the feed field where several probiotic effects have been reported. P. acidilactici was isolated from a vegetable source. It reduces food storage spoilage by inhibiting pathogens and putrefactive bacteria. This strain is very resistant to destruction by stomach acids. Animal research has shown that P. acidilactici is able to balance the intestinal microflora and reduce the risk of suboptimal health. Moreover, current results indicate that P. acidilactici is able to promote a healthy inflammatory response in the intestines, as well as support a healthy immune response. P. acidilactici produces several different antimicrobial compounds that lessen the number of pathogenic bacteria. It actively competes against Listeria. Lactococcus lactis ssp. lactis L. lactis species are common in food products ranging from kefir to Asian fermented vegetables. In the meat industry, L. lactis has been used for a long time due to its ability to inhibit the growth of spoilage bacteria, and it has been shown that kefir possesses antimicrobial activity against a wide variety of gram-positive and gram-negative bacteria, as well as against some fungi. Numerous studies have investigated the effects of kefir and kefir grains on supporting a healthy cell lifecycle. Special cultures isolated from kefir have been shown to bind to mutagenic substances, such as indole and imidazole.