Lactobacillus acidophilus (L. acidophilus) is part of a group of bacteria that live in the small intestine and vagina. Acidophilus is considered a probiotic. As a natural probiotic, acidophilus helps to stimulate the growth of beneficial bacteria in the digestive and intestinal tracts, encourages proper nutrient absorption and promotes immune health. There are as many as 100 trillion bacteria belonging to more than 400 species in the intestinal flora.
Natural Food Sources
The main dietary sources of Lactobacillus acidophilus include milk enriched with acidophilus, yogurt containing live L. acidophilus cultures, kefir, fermented soy products, tempeh and miso. L. acidophilus can also be taken in powder, liquid or capsule form as dietary supplements. A cidophilus is usually combined with bifidobacteria, and the resultant combination is commonly referred to as Acidophilus bifidus.
With more than 400 different bacteria living in the human gastrointestinal tract, the most common forms of intestinal probiotics are Bifidobacteria bifidum and Lactobacillus acidophilus. These bacteria act as balancing agents for non-friendly, pathogenic, gut-bacteria such as Escherichia coli or Candida. When the “friendly bacteria” are not present enough, a number of bacteria-related health problems such as digestive upset, headaches, sluggishness, irritability, cadidiasis can ensue. Yogurt, which contains Lactobacillus acidophilus, is usually recommended by practitioners to help reduce the adverse effects of oral antibiotic treatment.
L. acidophilus supports a favorable environment for the absorption of nutrients, encourages intestinal microflora balance, and promotes the healthy functioning of the intestinal system. Acidophilus has been used to treat or prevent vaginal yeast infections, yeast infections of the mouth, urinary tract infections and diarrhea caused by taking antibiotics. Some research has showed that acidophilus may provide additional health benefits, including improved gastrointestinal function, a boosted immune system, and a decrease in the frequency of vaginal yeast infections. Acidophilus is generally considered to be beneficial, as it produces vitamin K, lactase, and anti-microbial substances such as acidolin, acidolphilin, lactocidin, and bacteriocin.
A high acidophilus level creates an environment that is fatal to other dangerous bacteria such as streptococcus, salmonella and Escherichia coli. In one of the many research reports on acidophilus and gastrointestinal tract health, acidophilus was showed to have antimicrobial activities against pathogens and fungal microorganisms. Also since acidophilus is able to survive in environments of pH 4-5 or below, it is able to survive the harsh conditions of the stomach and pass through to the small intestine. A University of Nebraska study found that feed supplemented with acidophilus and fed to cattle resulted in a 61% diminution of Escherichia coli 0157:H7. Helicobacter pylori is a bacteria which infects just stomach tissues. This bacterium are responsible for more than 90% of duodenal ulcers and up to 80% of gastric ulcers. The presence of acidophilus appears to decrease H. pylori density in the human stomach and could enhance antibiotic treatment for Helicobacter pylori eradication. According to a study reported in the June 2002 edition of the Journal of the Medical Association of Thailand, the use of acidophilus preparation reduced the density of the Helicobacter pylori colonies in the stomachs of patients with stomach ulcers.
Bacterial vaginosis is the most important cause of vaginal discharge. Bacterial vaginosis is characterized by alteration of the normal vaginal microflora, in which a mixed anaerobic bacterial flora becomes prevalent over the population of lacobacilli. Tablets or suppositories containing live acidophilus cultures may help treat the problem of bacterial vaginosis. A study reported in the October 2012 edition of the Journal of Clinical Gastroenterology demonstrated that slow-release vaginal tablets containing acidophilus and another probiotic reduced symptoms of yeast infections in a group of women. In a study, women who consumed 8 ounces of L. acidophilus -containing yoghurt per day had a threefold decrease in the incidence of vaginal yeast infections and a reduction in the frequency of Candida colonization in the vagina. In another study, women with vaginal Trichomonas infection received vaginal L. acidophilus suppositories for one year. Over 90% of them were reported to be cured of their clinical symptoms in that time.
Lactose intolerance is the inability to digest important amounts of lactose the major sugar found in milk and milk products. Acidophilus milk has been used to treat people with lactose intolerance. Active bacteria cultures, such as acidophilus, may help treat lactose intolerance by producing an enzyme that helps digest the lactose sugars in intestines.A study in the “Journal of Family Practice” reviewed information on this and other probiotics as a potential therapy for lactose intolerance . The review suggested that acidophilus may work. The hydrogen breath test is the standard tool for diagnosing lactose intolerance. Strains of L. acidophilus demonstrated reduced amount of hydrogen. The authors concluded that, “…probiotics in general do not reduce lactose intolerance… However some evidence suggests that specific strains and concentrations are effective…”
Irritable bowel syndrome (IBS) is a very common functional condition. Many studies have found that probiotics may help relieve symptoms of irritable bowel syndrome. A review of previously published studies that appeared in the Aug 2009 edition of the “Revista Espanola de Enfermedades Digestivas” found that supplements with probiotics, (such as acidophilus), improves symptoms of IBS.
Some research suggests acidophilus may be useful when used to prevent traveler’s diarrhea. A mix of probiotics (Lactobacillus acidophilus, Bifidobacterium bifidum, and Saccharomyces boulardii) helped treat traveler’s diarrhea in one study. Taking acidophilus supplements may help maintain the health of gastrointestinal system, especially after taking a course of antibiotic drugs. While they can be efficacious at killing the “bad” germs, unhappily, antibiotics also destroy the “good” bacteria in our bodies as well. For years, acidophilus has been recommended by doctors to help control certain types of diarrhea, in particular diarrhea caused when oral antibiotics destroy the normal flora of the intestine. In an article in the May, 2012, edition of Journal of the American Medical Association, researchers reported that sufficient evidence exists to indicate that probiotics such as acidophilus can help treat antibiotic-associated diarrhea.