Also referenced as: Bifidobacterium spp., Lactobacillus Acidophilus, Lactobacillus species (spp.), Probiotics
Lactobacillus Acidophilus is a living anaerobic microorganism classified as a Probiotic. Probiotics are beneficial bacteria that positively alter the balance of intestinal microflora and are often referred to as colonic foods. These facultative anaerobes account for up to ten percent of the entire bacterial population in the intestinal tract. Lactobacillus Acidophilus is also found within the inner linings of the mouth and vagina. It enhances digestion and is involved in the production of acids, which make certain foods taste sour.
The use of Lactobacillus Acidophilus, Bifidobacterium species, and yeasts dates back to the time of Biblical writings. Probiotic use has also been documented in many other sacred works of religion, all of which differ from Christianity. The health-enhancing properties of these microorganisms were made known long before the many discoveries recognized by the modern sciences included within microbiology. The popularity of probiotics continues today in nutritional supplements and many functional foods, hence its inclusion in yogurt and other dairy products.
Recent study points to the beneficial properties of Probiotics like Lactobacillus Acidophilus. These microorganisms have been shown to benefit digestion, immunological functioning, and to inhibit the growth of harmful bacteria in the body.  This results from the breakdown of foods by Lactobacillus Acidophilus. The digestive processes of Lactobacillus Acidophilus effect the production of byproducts, such as lactic acid and hydrogen peroxide, which ultimately alter the gastrointestinal environment and discourage “bad” organisms from forming within our body.
*Probiotics differ from Prebiotics. The term Prebiotics refers to the soluble fiber that is found in a variety of food sources, which supports the production and development of probiotics within the GI (gastrointestinal) tract.*
The primary dietary sources of Lactobacillus Acidophilus are fermented dairy foods, and milk products enriched with acidophilus. Foods providing adequate amounts of acidophilus include live yogurt cultures, miso, and tempeh. These products vary greatly concerning the type of bacteria used and their individual potencies. Another source of probiotics include dried or liquid cultures of living bacteria made available in a variety of nutritional supplements. These cultures are often marketed as freeze-dried powders, granules, or capsules. Supplemental Lactobacillus Acidophilus is also offered in the form of a liquid, or included in probiotic extracts.
Adequate levels of probiotics, like Lactobacillus Acidophilus, may assist in the elimination of infectious, disease-causing bacteria and various viral induced conditions by increasing the amount of intestinal flora in the digestive tract.  Intestinal flora, or microflora, is responsible for the development of immune system and its accompanying inflammatory response properties. These microflora are also equally vital in inhibiting attachments of pathogenic organisms by producing intestinal mucosa; thereby increasing the body’s natural defense mechanisms.
Lactobacillus Acidophilus also increases immune system function by producing a substance called bacteriocin, which acts as a natural antibiotic in the eradication of potentially harmful organisms.  Probiotics are equally imperative in recolonizing beneficial bacteria to the intestines during, and after, synthetic antibiotic treatments. 
Certain gastrointestinal disorders like antibiotic-associated diarrhea, viral diarrheas, rotavirus-induced diarrhea, and inflammatory bowel disease, may derive benefit from Lactobacillus supplementation. [5, 6] Intestinal bacteria levels are rapidly depleted by the fluid loss caused by diarrhea, resulting in an increased risk for the development of opportunistic infections. Lactobacillus Acidophilus and other probiotics assist in the replenishment of these beneficial bacteria and decrease the risk for the onset of new infections. Probiotics may also reduce the risk of gastrointestinal disorders, which are common in persons who are lactose intolerant.  Lactobacillus Acidophilus provides a source of lactase, the enzyme responsible for the digestion of milk sugars.
Lactobacillus Acidophilus has been used as an alternative treatment for vaginitis. This specific probiotic has been effective in preventing candida overgrowth caused by yeast infections.  In an auxiliary study, women with recurrent candidal vaginitis were treated with yogurt over a six-month period. Eight ounces of yogurt consumed daily over this time period resulted in a dramatic decrease of both candidal colonization, and the occurrence of vaginal infection. 
Preliminary study suggests that Lactobacillus Acidophilus may yield antioxidant and cholesterol lowering properties. [10, 11] Study has also been conducted to determine the effectiveness of probiotics in reducing the incidence of specific forms of colon cancers.  Initial results into these uses of Lactobacillus remains promising, but more long-term study is warranted to validate these claims.
Various strains of probiotics are available for nutritional supplementation. There are no established or recommended dosages for probiotics, including Lactobacillus. The amount needed varies from individual to individual, and is often determined on the basis of prevention, microbial depletion (from antibiotic use), or due to the presence of harmful bacteria. Typical dosages range from one to ten billion colony-forming units (CFU) per week. The table below is an example of various uses and accompanying dosages for Lactobacillus Acidophilus:
|Health Condition:||Adults and Teenagers||Children up to age 12|
|Prevention of diarrhea||1 – 2 billion CFU daily||Follow label recommendations|
|Recolonization of Intestinal Microflora||5 – 10 billion CFU daily for a duration of 2 weeks||Follow label recommendations|
|Vaginal Infections||1 – 2 billion CFU daily ++||Not Applicable|
|Normal Maintenance||1 – 10 billion CFU daily||Follow label recommendations|
++ Women may also replace this supplemental dosage with 8 ounces of yogurt daily, containing live active cultures of a Lactobacillus or Bifidobacterium strain -
Although some mild gastrointestinal disturbances have been reported in individuals supplementing with more than 1- 2 billion Lactobacillus Acidophilus cells per day, probiotics are considered safe and are generally well tolerated. The most common adverse effects include flatulence and constipation.
Deficiencies of Lactobacillus Acidophilus, and other probiotics, may increase one’s susceptibility to certain bacterial infections and viruses. Low levels of these beneficial bacteria may also cause a decrease in the absorption efficiency of the digestive tract. This declination may lead to possible nutrient deficiencies.
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