Lactobacillus acidophilus


Lactobacillus acidophilus is a member of the Lactobacillus genus of bacteria. These bacteria can be found in the mouth, intestine, and vagina. L. acidophilus is thought to benefit health, since it produces vitamin K and lactase. However, L. acidophilus cannot make many other vitamins and amino acids. Because of this, L. acidophilus is mostly found in the upper gastrointestinal (GI) tract where there are higher amounts of these nutrients.
L. acidophilus is commonly used in food, such as yogurt, other dairy products, and fermented soy products, such as miso and tempeh.
L. acidophilus is one of the most commonly used probiotics, microorganisms that are used to promote health. Probiotics are different from prebiotics, which are complex sugars that may support the growth of "good" bacteria in the intestinal tract. The word "synbiotic" means that a product has both a probiotic and a prebiotic.
There is good evidence for the use of L. acidophilus in treating vaginal infections. However, there is unclear evidence for other medicinal uses of L. acidophilus, such as in irritable bowel syndrome, brain disorders, asthma, high cholesterol, lactose digestion, or diarrhea.
Although it is thought to be safe with few side effects, L. acidophilus by mouth should be avoided in people who have intestinal damage, immune problems, or an overgrowth of bacteria in the intestines. These people may have a higher risk of having the bacteria leave the GI tract and possibly cause multiple organ failure. There have been reports that some Lactobacillus species, such as L. rhamnosus and L. casei, may be involved in infections, such as abscesses, meningitis, and septic arthritis.

Related Terms

Acidophilus, Acidophilus Extra Strength®, acidophilus milk, Acilact, Actimel® Cholesterol Control, Bio-K+®, Calagin®, DDS-Acidophilus, Enpac®, Florajen®, fresh poi, Kyo-Dophilus®, L-92, L. amylovorus, L. gallinarum sp. nov. (ATCC 33199), L. johnsonii sp. nov. (ATCC 33200), Lacteol Fort®, lactic acid bacteria mixture (Oxadrop® or AKSB), lactic acid-producing bacteria (LAB), Lacto Bacillus, Lactobacillaceae (family), lactobacilli, lactobacilo acidofilo, lactobacillus, Lactobacillus acidophilus, Lactobacillus acidophilus 74-2, Lactobacillus acidophilus 145, Lactobacillus acidophilus ATCC 4356, Lactobacillus acidophilus B, Lactobacillus acidophilus BG2F04, Lactobacillus acidophilus CL1285, Lactobacillus acidophilus CUL60, Lactobacillus acidophilus DDS-1, Lactobacillus acidophilus E, Lactobacillus acidophilus group A3, Lactobacillus acidophilus L-92, Lactobacillus acidophilus LA 02, Lactobacillus acidophilus La5, Lactobacillus acidophilus milk, Lactobacillus acidophilus N1, Lactobacillus acidophilus NCFM, Lactobacillus acidophilus NCK56, Lactobacillus acidophilus OLL2769, Lactobacillus acidophilus Rosell-52, Lactobacillus acidophilus spp., Lactobacillus acidophilus strain 27L, Lactobacillus acidophilus strain LB (LaLB), Lactobacillus acidophilus-SDC 2012, Lactobacillus acidophilus-SDC 2013, Lactobacillus acidophilus yogurt, Lactobacillus amylovorus, Lactobacillusgallinarum sp. nov. (ATCC 33199), Lactobacillus johnsonii sp. nov. (ATCC 33200), Lactobacillus LB, Narine®, poi, Probiata®, probiotic, sour poi, Vitaflor, Vivag®, yogurt.
Combination products containing L. acidophilus : Bacid®, Bifid Triple Viable (Lactobacillus acidophilus, Bifidobacterium bifidum, and fecal streptococci), Cultura®, Dentavax (D) (composed of killed cells from Klebsiella pneumoniae, Streptococcus pyogenes, Staphylococcus aureus, Candida albicans, L. acidophilus, and their lysates), Endolac ®, Femilac® (containing L. rhamnosus, L. delbrueckii, L. acidophilus, and Streptococcus thermophilus), Fermalac® (Canadian), Gynatren® (L. acidophilus, boric acid, and vitamin C), Gynoflor® (L. acidophilus and estriol), Infloran® (L. acidophilus and Bifidobacterium infantis), Kala®, Lactinex™, More-Dophilus®, NY-YP901 (Streptococcus thermophilus, Lactobacillus acidophilus, Bifidobacterium infantis, Bifidobacterium breve (CBG-C2), Enterococcus faecalis FK-23, and fibersol-2), Oxadrop®, Pro-Bionate®, Probaclac Vaginal (Lactobacillus rhamnosus, Lactobacillus acidophilus, and Streptococcus thermophilus), Probio-Stick™ (Lactobacillus acidophilus Rosell-52 and Bifidobacterium longum Rosell-175), SCM-III (L. acidophilus strain 145, L. helveticus ATC 15009, Bifidobacterium), Superdophilus®, and VSL3# (three strains of Bifidobacterium, four strains of Lactobacillus, including L. acidophilus, and one strain of Streptococcus).
Note: This bottom line does not provide an in-depth analysis of L. acidophilus used in combination therapies. When available, studies using L. acidophilus alone are discussed in detail.

evidence table

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
Vaginal disorders (Grade: B)
There is good evidence supporting the use of
Allergic skin reactions (Grade: C)
Anemia (Grade: C)
Limited research shows that
Ankylosing spondylitis (Grade: C)
Limited research suggests that a probiotic combination containing
Asthma (Grade: C)
Limited research found unclear and negative evidence to support the use of
Cavities (Grade: C)
Limited research shows that eating probiotic ice cream containing
Diabetes (type 2) (Grade: C)
Limited research suggests that taking capsules containing
Diarrhea prevention (Grade: C)
It is unclear whether
Diarrhea treatment (children) (Grade: C)
The World Health Organization (WHO) reports that treating acute diarrhea in children involves drinking plenty of fluids and supplementing with heat-killed
Eye diseases (Grade: C)
Low-quality studies found that eyedrops that contain
Flu (Grade: C)
Limited research suggests that
Hay fever (Grade: C)
Animal research suggests that
Helicobacter pylori infection (Grade: C)
Some strains of probiotic bacteria may block the growth
Hepatic encephalopathy (Grade: C)
One study found that probiotics containing
Immune function (Grade: C)
Probiotics may help enhance the immune system at an early age and prevent allergic disorders later in life. Combination probiotic supplements have been shown to affect the adult immune system. Early studies found that
Intestinal disorders (Grade: C)
Studies report that combination probiotic preparations containing
Lactose intolerance (Grade: C)
Lactic acid bacteria are thought to promote lactose digestion by breaking down lactose or releasing compounds that help digest it. However, there is unclear and conflicting evidence to support the use of
Liver disease (Grade: C)
Limited research using a combination treatment has shown that probiotic treatment may improve the symptoms of liver disease in certain patients, but further studies are still needed before conclusions may be made. In addition, studies assessing the effects of
Necrotizing enterocolitis (NEC) prevention (Grade: C)
Limited research suggests that treating newborns with solutions containing living or killed
Pneumonia (Grade: C)
Limited research shows that pneumonia has been treated with a combination of antibiotics and
Pouchitis (Grade: C)
Limited research suggests that a combination therapy involving
Pregnancy problems (Grade: C)
Vaginal disease caused by bacteria may lead to preterm delivery and low birthweight. There is some evidence that
Radiation-induced diarrhea (Grade: C)
Limited research shows that diarrhea caused by radiation may be reduced with combination therapy involving
Sepsis (Grade: C)
Limited research shows that treating newborns with solutions containing living or killed
High cholesterol (Grade: D)
There is conflicting evidence as to whether combination probiotics containing