Lactobacillusacidophilus (L. acidophilus) is the most commonly used probiotic, or "friendly" bacteria. Many healthy bacteria live in the intestines and vagina, where they protect against "bad" bacteria that can cause disease. They do this in a couple of ways: for example, when L. acidophilus breaks down food in the intestine, several substances are formed (such as lactic acid and hydrogen peroxide) that create an unfriendly environment for “bad” bacteria. Probiotics are often suggested as a supplement when you take antibiotics. Antibiotics kill bacteria, but don’t discriminate between “friendly” and “unfriendly” organisms, so the balance between good and bad bacteria in the intestines can be upset. It is thought that taking probiotics helps restore the healthy balance of bacteria.
Other probiotics include several Lactobacillus species (spp.), such as L. bulgaricus, L. casei, and L. reuteri, Lactobacillus GG,Bifidobacterium longum, Bifidobacterium bifidum, Streptococcus thermophilus, and Saccharaomyces boulardii (a kind of yeast).
In addition to probiotics, some health care providers suggest taking “prebiotics.” These are the soluble fiber found in some foods or supplements that help prebiotics thrive in the intestine. Examples include fructooligosaccharides (FOS), a carbohydrate found in some fruits and vegetables.
Probiotics may be used for the following:
Several clinical studies suggest that using L. acidophilus vaginal suppositories can help treat bacterial vaginosis. A small number of clinical studies suggests that eating yogurt with L. acidophilus cultures may also help. Some people also use L. acidophilus to treat or prevent vaginal yeast infections, although the evidence about whether it is effective is mixed. Additional clinical research is needed.
The evidence for using Lactobacillus to prevent diarrhea is mixed. Some clinical research suggests Lactobacillus acidophilus may be effective when used to prevent traveler’s diarrhea (caused by eating contaminated food). Other studies have found that Lactoabcillus GG was effective. A mix of probiotics (Saccharomyces boulardii and a mixture of Lactobacillus acidophilus and Bifidobacterium bifidum) helped treat traveler’s diarrhea in one study.
Probiotics, especially Lactobacillus GG, may help prevent or treat infectious diarrhea in children and adults, although the evidence is mixed. Studies seem to show probiotics are most effective in treating rotavirus in children. Diarrhea in children can be serious, and you should call your doctor if it lasts more than a day or your child seems dehydrated.
Other studies have found that probiotics, taken regularly, may help prevent gastrointestinal infections in adults.
Several studies suggest that probiotics, especially Lactobacillus GG and S boulardi, may help prevent diarrhea associated with taking antibiotics. Antibiotic-related diarrhea can be serious, so you should tell your doctor about it.
Lactobacillus and other probiotics have been suggested for a number of conditions, although evidence in most cases is preliminary or mixed:
- Replacing the "friendly" intestinal bacteria destroyed by antibiotics
- Helping digestion and suppressing disease causing bacteria
- Treating chronic constipation
- Treating symptoms of irritable bowel syndrome and inflammatory bowel disease (such as Crohn's disease and ulcerative colitis)
- Improving lactose tolerance in people who are lactose intolerant
- Enhancing the immune system. Studies have suggested that consuming yogurt or milk that contains specific strains of Lactobacillus or taking supplements with Lactobacillus or Bifidobacterium may improve the body’s natural immune response. One study found that supplementation for 6 months was a safe, effective way to reduce fever, cough, and duration of antibiotic treatment, as well as number of missed school days for children 3 - 5 years of age
- Lowering risk of pollen allergies
- Reducing the risk of childhood eczema
- Helping to treat high cholesterol
Newborns and Infants (0 - 1 year): Always check with your pediatrician before giving dietary supplements to an infant or child. Topical forms are available that may be used for diaper rash. If your infant is taking antibiotics, ask your doctor if a probiotic supplement might be appropriate as well.
Recommended doses of L. acidophilus vary depending on the health condition being treated. Check the specific dosage recommendations on the product label. The following lists guidelines for the most common uses:
For prevention or treatment of diarrhea: Take 1 - 2 billion colony forming units or CFUs per day. Some health care providers may recommend up to 10 - 15 billion cells per day.
For vaginal infections: Some supplement manufacturers offer a probiotic suppository for vaginal use. Many people recommend inserting regular probiotic capsules vaginally as well. However, oral medications should be taken orally and those seeking a vaginal application should look for formulas specifically designed for vaginal use. Many practitioners rely on the oral use of probiotics to treat and prevent vaginal infections without using any sort of vaginal application of probiotics. You should never insert prebiotics vaginally. Speak with your physician.
For maintaining intestinal health: Take 1 - 15 billion CFUs daily in healthy adults. If for the prevention of antibiotic related diarrhea, some health care providers recommend taking it 2 - 3 hours after the antibiotic.
If diarrhea occurs, decrease the dosage or stop taking the product and talk with your health care provider.
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