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Probiotics

What are probiotics?

Probiotics are bacteria that help keep the natural balance of organisms (microflora) in the intestines camera.gif. The normal human digestive tract contains about 400 types of probiotic bacteria that reduce the growth of harmful bacteria and promote a healthy digestive system. The largest group of probiotic bacteria in the intestine is lactic acid bacteria, of which Lactobacillus acidophilus, found in yogurt, is the best known. Yeast is also a probiotic substance. Probiotics are also available as dietary supplements.

It has been suggested that probiotics be used to treat problems in the stomach and intestines. But only certain types of bacteria or yeast (called strains) have been shown to work in the digestive tract. It still needs to be proved which probiotics (alone or in combination) work to treat diseases. At this point, even the strains of probiotics that have been proved to work for a specific disease are not widely available.

Recommended Related to Digestive Disorders

Chronic Constipation: Facts vs. Myths

Constipation, the most common digestive complaint in the U.S. population, can make life miserable. Not only does constipation make you feel bloated, headachy, and irritable, but relieving constipation -- especially long-term or chronic constipation -- is time consuming and expensive. Each year in the U.S., chronic constipation leads to around 2.5 million doctor visits -- and medication costs of many hundreds of millions of dollars.

Read the Chronic Constipation: Facts vs. Myths article > >

What are probiotics used for?

Many people use probiotics to prevent diarrhea, gas, and cramping caused by antibiotics. Antibiotics kill "good" (beneficial) bacteria along with the bacteria that cause illness. A decrease in beneficial bacteria may lead to digestive problems. Taking probiotics may help replace the lost beneficial bacteria. This can help prevent diarrhea.

A decrease in beneficial bacteria may also lead to other infections, such as vaginal yeast and urinary tract infections, and symptoms such as diarrhea from intestinal illnesses.

Probiotics may also be used to:

  • Help with other causes of diarrhea.
  • Help prevent infections in the digestive tract.
  • Help control immune response (inflammation), as in inflammatory bowel disease (IBD).

Probiotics are being studied for benefits in colon cancer, skin infections, and irritable bowel syndrome (IBS).

Are probiotics safe?

Most probiotics are like what is already in a person's digestive system. Some probiotics have been used for a very long time throughout history, such as in fermented foods and cultured milk products. They don't appear to cause illness. But more study is needed on the safety of probiotics in young children, the elderly, and people who have weak immune systems.

As with any dietary supplement, be aware that probiotic supplements are regulated as foods, not drugs. Tell your doctor about everything you are taking, including the specific bacteria in your probiotic supplement.

By Healthwise Staff
Primary Medical Reviewer Adam Husney, MD - Family Medicine
Specialist Medical Reviewer Marc S. Micozzi, MD, PhD - Complementary and Alternative Medicine
Last Revised June 29, 2011

WebMD Medical Reference from Healthwise

Last Updated: June 29, 2011
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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