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Probiotics - Natural Medicine A-Z
Probiotics
Synonyms: AB-yogurt, acidophilus, acidophilus milk, antibiophilus, Bacillus, bifidobacteria, Bifidobacterium animalis ssp. lactis (BB-12), Bifidobacterium DN-173 010, Enterococcus, Enterococcus faecium M-74, Escherichia, fermented soymilk, flora, fructo-oligosaccharides (FOS), Helicobacter pylori, L. acidophilus milk, L. acidophilus yogurt, lactic acid bacteria, lacto bacillus, Lactobacillaceae (family), lactobacilli, Lactobacillus, Lactobacillus casei DN-114 001, Lactobacillus casei shirota, Lactobacillus coryniformis CECT5711, Lactobacillus gasseri CECT5714, Lactobacillus johnsonii LA1, Lactobacillus rhamnosus GR-1, Lactobacillus paracasei ssp. paracasei (CRL-431), Lactobacillus reuteri B-54 and RC-14, Lakcid L, oligofructose, oral bacteriotherapy, prebiotic, Saccharomyces boulardii, VSL#3, yogurt.
 Overview Does It Work? Safety How to Use

Probiotics are beneficial bacteria (sometimes referred to as "friendly germs") that help to maintain the health of the intestinal tract and aid in digestion. They also help keep potentially harmful organisms in the gut (harmful bacteria and yeasts) under control. Most probiotics come from food sources, especially cultured milk products. Probiotics can be consumed as capsules, tablets, beverages, powders, yogurts, and other foods.

Probiotics should not be confused with prebiotics. Prebiotics are complex sugars (such as lactulose, lactitol, a variety of fructo-oligosaccharides, and inulin) that are used as fuel by the healthful bacteria to stimulate their growth and activity while suppressing the growth and activity of harmful organisms. Other foods that may support probiotic activity include Japanese miso, tempeh, kefir, raw milk, kombucha, bananas, garlic, and onions. When prebiotics and probiotics are combined in one product, it is called a synbiotic.

Probiotics are thought to work by colonizing the small intestine and crowding out disease-causing organisms, thereby restoring proper balance to the intestinal flora. They compete with harmful organisms for nutrients and may also produce substances that inhibit growth of harmful organisms in the gut.

Probiotic bacteria have been found to stimulate the body's immune system. They may also aid in several gastrointestinal illnesses such as inflammatory bowel diseases, antibiotic-related diarrhea, Clostridium difficile toxin-induced colitis, infectious diarrhea, hepatic encephalopathy, irritable bowel syndrome, and allergy.

Probiotics have been found to enhance the digestion and absorption of proteins, fats, calcium, and phosphorus. They may help overcome lactose intolerance. Finally, they may help restore healthful bacteria after a course of antibiotic therapy has altered the normal gastrointestinal flora.

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.

Uses

Grade*

Antibiotic (probiotics to reduce related adverse effects)

An increasing number of studies support the use of probiotics as a supplement to antibiotic therapy. Probiotic supplementation during a course of antibiotics may reduce the adverse effects of antibiotics in the intestinal environment. This includes reducing growth of Clostridium difficile bacteria, which can lead to colitis, a common complication of antibiotics, especially in the elderly. Some probiotics may also help prevent the development of antibiotic resistance. In acutely ill children, synbiotics have been linked to greater weight gain and fewer bacterial illnesses after antibiotics are ended. The evidence consistently supports supplementation of antibiotics.

A

Atopic dermatitis (eczema)

Probiotics show promise for preventing atopic eczema/dermatitis syndrome in children. Infants benefit when their mothers take probiotics during pregnancy and breastfeeding. Direct supplementation of infants may reduce the incidence of atopic eczema by as much as half. It may also reduce cow's milk allergy and other allergic reactions during weaning. Probiotics may stabilize the intestinal barrier function and decrease gastrointestinal symptoms in children with atopic dermatitis. Children do differ, however, in their responsiveness to specific probiotics. The effectiveness of probiotics for the treatment of eczema is still under investigation.

A

Helicobacter pylori infection

Antibiotics are the main treatment to eradicate Helicobacter pylori, the cause of most stomach ulcers. Side effects commonly include bloating, diarrhea, and taste disturbances. Probiotics reduce these side effects and generally help people tolerate the treatment. They may also reduce levels of H. pylori in children and adults. Yogurt containing probiotics suppresses H. pylori infection and may lead to more complete eradication during antibiotic treatment.

A

Cirrhosis

Liver cirrhosis may be accompanied by an imbalance of intestinal bacteria flora. Probiotic supplementation in cirrhosis patients has been found to reduce the level of fecal acidity (pH) and fecal and blood ammonia, which are beneficial changes.

B

Colon cancer

There is recent evidence that supplementation with Lactobacillus casei may help reduce the recurrence of colorectal tumors in patients who have previously undergone surgery for colon cancer.

B

Dental caries

Short-term consumption of probiotic-containing cheese may benefit dental caries. There is also evidence that the probiotic Lactobacillus rhamnosus GG, when added to milk, may help reduce dental carries in young children.

B

Diarrhea in children (nosocomial)

Lactobacillus GG may reduce the risk of nosocomial (originating in a healthcare setting) diarrhea in infants, particularly cases caused by rotavirus gastroenteritis.

B

Diarrhea prevention

There is tentative support for probiotics to prevent diarrhea in adults and children. Supplementation may benefit HIV-positive men, and yogurt containing Lactobacillus casei may help reduce incidence in healthy young adults. Children may benefit from Bifidobacterium lactis (strain Bb 12) added to their formula.

B

Diarrhea treatment (children)

Probiotics may reduce the duration of diarrhea and related hospital stays in children. Fermented formula and formula supplemented with probiotics may reduce both the number and duration of episodes of diarrhea.

B

Growth

There is evidence that young children (ages 6-36 months) who receive infant formula with bifidobacteria Bb12 supplementation may achieve faster growth than without the supplementation.

B

Immune enhancement

Research suggests that probiotics, especially those in milk or food, may help boost the immune system. However, commercially produced yogurt may not be as effective. More studies are needed, particularly with yogurt, to give recommendations.

B

Infections (gastrointestinal/respiratory)

Limited evidence with day care children suggests supplementation with Lactobacillus GG may reduce number of sick days, frequency of respiratory tract infections, and frequency of related antibiotic treatments. Fermented milk (with yogurt cultures and L. casei DN-114001) may reduce the duration of winter infections (gastrointestinal and respiratory), as well as average body temperature, in elderly people.

B

Infectious diarrhea

Probiotics may reduce duration of symptoms in adults and children with infectious diarrhea by 17 to 30 hours. Effective forms include Lactobacillus strain GG, Lactobacillus reuteri, combination Lactobacillus rhamnosus and Lactobacillus reuteri, and combination Lactobacillus acidophilus and Lactobacillus bifidus. More studies are needed to evaluate types, dosages, duration of treatment, and relationships to specific pathogens.

B

Irritable bowel syndrome (IBS)

Many types of probiotics have been shown to moderately reduce symptoms of IBS, including pain, gas, bloating, and stool frequency. There is also some evidence that probiotics may reduce swelling and improve quality of life. However, not all studies show beneficial effects.

B

Pancreatitis (acute)

Supplementing with Lactobacillus plantarum 299 may help prevent pancreatic infection (sepsis), reduce the number of operations needed, and reduce the length of hospital stay in treatment of acute pancreatitis.

B

Radiation-induced colitis/diarrhea

Probiotics may help treat or prevent radiation-induced diarrhea in cancer patients.

B

Sinusitis (hypertrophic)

Use of probiotic Enterococcus faecalis bacteria in hypertrophic sinusitis (sinus inflammation) may reduce frequency of relapses and the need for antibiotic therapy.

B

Ulcerative colitis

E. coli Nissle 1917 appears to be as effective as the drug mesalazine, but is not currently available in the United States. A variety of Bifidophilus preparations have shown effects of preventing relapse or maintaining remission. These include Bifidophilus alone, Bifidophilus in fermented milk products, and a synbiotic preparation. A probiotic combination consisting of VSL#3 plus balsalazide may be more effective than balsalazide or mesalazine alone. More studies are needed to more clearly determine what outcomes can be expected.

B

Allergy

There is promising early evidence that probiotics may help treat allergic conditions, especially allergic skin disorders in infants. Most studies have tested probiotics in children, teenagers, and young adults. Some evidence also suggests that probiotics help reduce swelling caused by allergies. However, study results are mixed for inhalant allergies, such as allergic rhinitis (nasal inflammation and discharge).

C

Amoebiasis

Combining a probiotic yeast (Saccharomyces boulardii) with antibiotics in the treatment of acute amoebiasis (amoebic dysentery) may decrease the duration of symptoms. More studies are needed to determine recommendations for probiotics in acute amoebiasis.

C

Asthma

Laser acupuncture plus probiotics may help prevent asthma attacks in school-aged children with intermittent or mild persistent asthma. More research with probiotics alone is needed.

C

Bacterial infection

As a bacterial reservoir, the nose may harbor many varieties of potentially disease-causing bacteria. There is limited evidence that probiotic supplementation may reduce the presence of harmful bacteria in the upper respiratory tract. More studies are needed to establish this relationship and its implications for health.

C

Bacterial vaginosis

Vaginal suppositories containing probiotics may be effective in the treatment or prevention of bacterial vaginosis. Eating yogurt enriched with Lactobacillus acidophilus may also be beneficial. However, not all applications of probiotics show benefit. Additional research is necessary before firm conclusions can be reached regarding what probiotics and what methods can lead to reliable results.

C

Cardiovascular disease

There is limited evidence suggesting probiotics may help reduce low density lipoprotein (LDL or "bad") cholesterol, a risk factor for cardiovascular disease, in overweight people. These findings are tentative and more evidence is needed to arrive at firm conclusions.

C

Cardiovascular risk reduction (smokers/atherosclerosis)

One study suggests probiotic supplementation might reduce blood pressure and some biochemical risk factors for cardiovascular disease (leptin and fibrinogen). This implies a possible protective effect against atherosclerosis. However, more studies are needed to confirm such effects.

C

Colitis (collagenous)

There is not enough evidence on which to form conclusions for the use of probiotics in collagenous colitis.

C

Constipation

Use of probiotics with constipation has had mixed results. Some research suggests that they may help reduce symptoms in patients with long-term constipation. However, another study did not show effectiveness in young children. More studies are needed to determine what forms of probiotics might be effective in constipation.

C

Diarrhea (acute)

Probiotics may help treat acute diarrhea. Saccharomyces boulardii and a probiotic formula Escherichia coli Nissle 1917 (EcN) solution have been shown to moderately improve diarrhea in children. However, all probiotic preparations may not be effective.

C

Diarrhea (antibiotic-associated)

Although some data support the use of probiotics for the treatment and prevention of antibiotic-associated diarrhea (AAD), other studies have found a lack of benefit. Although probiotics are considered a safe and reasonable approach for AAD, larger and better-designed studies are needed for definitive recommendations.

C

Diarrhea (chronic bacterial overgrowth-related)

There is limited evidence suggesting probiotics might help in the treatment of bacterial overgrowth-related chronic diarrhea. More studies are needed to provide guidelines for this use.

C

Diarrhea (Clostridium difficile)

There is limited evidence suggesting that probiotics may reduce recurrence of Clostridium difficile after antibiotic therapy. However, more studies are needed to provide definitive guidelines about this use.

C

Ear infections

Probiotic capsules (containing Lactobacillus rhamnosus GG and LC705, Bifidobacterium breve 99 and Propionibacterium freudenreichii JS) did not protect against ear infections in children. More research is needed to confirm these findings.

C

Hepatic encephalopathy (confused thinking due to liver disorders)

Initial studies in minimal hepatic encephalopathy are encouraging. Probiotics and prebiotics may lead to the improvement of symptoms and may be an alternative to lactulose for the management of this condition in people with cirrhosis. However, more studies are needed to determine the role of probiotics in this condition.

C

High cholesterol

There is conflicting evidence regarding the effects of probiotic-enriched dairy products on lowering blood levels of total cholesterol or low-density lipoprotein ("bad cholesterol"). More studies are needed.

C

Infections (complications)

Results are mixed regarding the ability of probiotics to reduce infective complications of medical treatment. Reduced incidence of infection has been seen in patients treated for brain injury, abdominal surgery, and liver transplantation. Other studies have shown no such reduction in elective abdominal surgery and critical care patients.

C

Infections (rotavirus nosocomial)

Children receiving Bifidophilus-supplemented milk-based formula may be protected against rotavirus infection. Lactobacillus GG has shown mixed results, while early evidence suggests that L. rhamnosus is not effective. Some studies suggest shorter duration of diarrhea, less chance of a protracted course, and faster discharge from the hospital with Lactobacillus GG, while others suggest it is ineffective compared to breastfeeding. More studies are needed to determine the optimal use of probiotics in rotavirus nosocomial infection.

C

Inflammatory bowel disease (IBD)

It is unclear if probiotics can help treat inflammatory bowel disease (IBD). Study results are mixed. Saccharomyces boulardii, E. coli Nissle, probiotics, yogurt, and high doses of probiotics have shown the most promise. More research is needed.

C

Lactose intolerance

Supplementation of infant formulas with probiotics is a potential approach for the management of cow's milk allergy, but there is conflicting evidence as to whether it improves digestion of lactose. More research is needed in this area before a conclusion can be drawn.

C

Necrotizing enterocolitis (NEC) prevention

Little evidence is available on the effects of probiotics in the prevention of NEC. Study results conflict. Further studies are needed to determine the effectiveness of this application.

C

Nutrition

Fermented milk containing the probiotic L. johnsonii La1 may improve nutritional status in the elderly. More research is needed to confirm these results.

C

Peptic ulcers

Early research suggests that probiotics may help prevent peptic ulcers. However, more research is needed to determine if this is an effective therapy.

C

Pneumonia

There is insufficient evidence to draw any firm conclusions. More research is necessary.

C

Pouchitis

Limited evidence suggests a probiotic preparation (VSL#3, containing lactobacilli, bifidobacteria, and Streptococcus salivarius subspecies thermophilus) may be effective in the prevention of pouchitis. Notably, discontinuation appears to be followed by relapse, while continuation apparently maintains remission and better quality of life. Lactobacillus GG supplementation, however, has had conflicting results in preventing flare-ups. More studies are needed to arrive at concrete recommendations.

C

Premature labor prevention

There is not enough evidence to determine if probiotics can help prevent preterm birth and its complications.

C

Rheumatoid arthritis (RA)

In a small study, Lactobacillus GG was associated with improved subjective well-being and trends in reduced symptoms, though not statistically significant. More studies on the effects of probiotics in RA are needed.

C

Supplementation in preterm and very low birthweight infants

Probiotics, when added to formulas or breast milk, may foster better growth and higher counts of healthful bacteria in the gut of preterm infants. They may also boost the immune system and improve feeding tolerance. However, Lactobacillus GG may not be effective. More studies are needed to clarify specific guidelines for probiotics in preterm infant care.

C

Thrush

Early research suggests that cheese-containing probiotics may help reduce the risk of a fungal mouth infection, called thrush, in the elderly. More research is needed in this area.

C

Urinary tract infection

Studies of Lactobacillus preparations have had mixed results. Evidence suggests a combination of Lactobacillus rhamnosus GR-1 and L. fermentum RC-14 may reduce potentially harmful vaginal bacteria and yeast in healthy women. Other studies have found no benefit for women or pre-term infants. More studies are needed to determine the effectiveness of probiotics in urinary and urogenital tract infections.

C

Vaccine adjunct

Lactobacillus fermentum (CECT5716) may increase the protective effects of the flu vaccine. More research is needed.

C

Vaginal candidiasis (yeast infection)

Probiotics have not been adequately studied for the prevention or treatment of vaginal yeast infections. More research is needed in this area before a conclusion can be drawn.

C

Bacterial infection (translocation)

Bacterial translocation (passage of bacteria from the gut to other areas of the body where they can cause disease) is of special concern in surgery. Limited evidence suggests that supplementation with probiotics may not reduce this problem.

D

Diarrhea (HIV patients on antiretroviral therapy)

Probiotic therapy is well tolerated in HIV infected patients on antiretroviral therapy, but may not be helpful for gastrointestinal symptoms.

D

Fertility

Probiotics have been used in the vagina immediately after oocyte retrieval during IVF, but they do not appear to have an effect on vaginal colonization or pregnancy rate in IVF cycles.

D

*Key to grades

  • A: Strong scientific evidence for this use
  • B: Good scientific evidence for this use
  • C: Unclear scientific evidence for this use
  • D: Fair scientific evidence for this use (it may not work)

Many complementary techniques are practiced by healthcare professionals with formal training, in accordance with the standards of national organizations. However, this is not universally the case, and adverse effects are possible. Due to limited research, in some cases only limited safety information is available.

Allergies

Probiotics are often found in yogurt, milk and dairy products. Caution is advised in patients sensitive or intolerant to dairy products containing probiotics.

Side Effects and Warnings

Probiotics are generally regarded as safe for human consumption. Long-term consumption of probiotics is considered safe. Few side effects have been reported in studies.

Some people experience excessive production of gas due to the corrective activity of probiotics in the colon. This is patient-specific and normally will decrease with use. Gradual increase of dosing over time is recommended to minimize this effect.

Probiotics should not be taken in people who are allergic to any component of a probiotic-containing product. Lactose-sensitive people may develop abdominal discomfort from dairy products containing probiotics. Caution is advised when using probiotics in neonates born prematurely or with immune deficiency.

Pregnancy and Breastfeeding

Although probiotics (when consumed as dairy products or yogurt) appear safe during pregnancy and breastfeeding, additional study is needed to confirm these findings. Caution is advised when using probiotics in neonates born prematurely or with immune deficiency.

Adults (over 18 years old)

Probiotics are commercially available as capsules, yogurts, powder, and dairy products. Various doses have been studied, however, additional study is needed to confirm the effectiveness of these doses. The most common probiotics are Lactobacillus, Saccharomyces and Bifidobacterium.

To reduce side effects when taking antibiotics, 100 grams of a probiotics drink containing Lactobacillus casei, Lactobacillus bulgaricus, and Streptococcus thermophilus has been taken twice daily in combination with antibiotics. The drink was continued for one week after the antibiotics were finished.

Children (under 18 years old)

Various doses and probiotic strains have been studied in children. Children (3-24 months of age) have taken Saccharomyces boulardii for six days for the treatment of diarrhea. Children (2-47 months old) have also taken Escherichia coli Nissle 1917 (EcN) solution daily. The specific dose of EcN depended on the child's weight. One capsule of Lactobacillus rhamnosus strain GG (Culturelle, ConAgra Foods, Omaha, NE) has also been taken daily. Additional study is needed to confirm the effectiveness of these doses.

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