Probiotics

• Introduction to probiotics
• What is important to know about probiotics?
• What are probiotics, and which foods contain probiotics?
• What are the health benefits of probiotics?
• Do probiotics actually work?
• What are the side effects and risks of probiotics?
• Is there anything to take into consideration when taking probiotics?
• What research is being done on probiotics?
• Where can a person get more information about probiotics?

"Good" Bacteria Foods: Health or Hype? Probiotics may be a healthy addition to your diet By Kathleen Zelman, MPH, RD, LD WebMD Weight Loss Clinic - Expert Column March 10, 2006 -- There has been a significant buzz on television commercials and in the media making a strong case that everyone needs to add probiotics into their diets for good health. Faith Popcorn, trend predictor, noted probiotics as one of the hottest food trends for 2006. Are you confused by terms like probiotics that sound more like a chemistry experiment than a dietary supplement? You're not alone. Probiotics are the latest in the category of good-for-you foods. Basically, they are "good" bacteria added to foods or occurring naturally in certain yogurts, fermented dairy drinks, and in supplement form. Probiotics have been used as a form of treatment for a variety of gastrointestinal diseases including irritable bowel, lactose intolerance, traveler's diarrhea, and antibiotic-induced diarrhea. How do they work? Scientists are not exactly sure but surmise that the good bacteria replace or crowd out the germs or bad bacteria in the intestinal tract. Another theory is that the good bugs keep the intestinal tract acidic where bad bugs can't survive. Our digestive tracts are lined with more than 400 different kinds of good bacteria that help fight off infection and keep us healthy. The largest group of good bacteria is the one found in yogurt. By consuming foods with probiotics, you can increase the number of healthy bacteria, boost your immunity, and promote a healthy digestive system. Which probiotics should you try? » Top Searched Probiotics Terms: foods that contain probiotics, IBS, allergies, vaginitis, irritable bowel syndrome, prebiotics

Introduction

Probiotics are live microorganisms (in most cases, bacteria) that are similar to beneficial microorganisms found in the human gut. They are also called "friendly bacteria" or "good bacteria." Probiotics are available to consumers mainly in the form of dietary supplements and foods. They can be used as complementary and alternative medicine (CAM). To find out more about topics and resources mentioned in this fact sheet, see "For More Information."

Key points

• People use probiotic products as CAM to prevent and treat certain illnesses and support general wellness.



• There is limited evidence supporting some uses of probiotics. Much more scientific knowledge is needed about probiotics, including about their safety and appropriate use.



• Effects found from one species or strain of probiotics do not necessarily hold true for others, or even for different preparations of the same species or strain.



• Tell your health care providers about any CAM practices you use. Give them a full picture of what you do to manage your health. This will help ensure coordinated and safe care.

What probiotics are

Experts have debated how to define probiotics. One widely used definition, developed by the World Health Organization and the Food and Agriculture Organization of the United Nations, is that probiotics are "live microorganisms, which, when administered in adequate amounts, confer a health benefit on the host." (Microorganisms are tiny living organisms—such as bacteria, viruses, and yeasts—that can be seen only under a microscope.)

Probiotics are not the same thing as prebiotics—nondigestible food ingredients that selectively stimulate the growth and/or activity of beneficial microorganisms already in people's colons. When probiotics and prebiotics are mixed together, they form a synbiotic.

Probiotics are available in foods and dietary supplements (for example, capsules, tablets, and powders) and in some other forms as well. Examples of foods containing probiotics are yogurt, fermented and unfermented milk, miso, tempeh, and some juices and soy beverages. In probiotic foods and supplements, the bacteria may have been present originally or added during preparation.

Most probiotics are bacteria similar to those naturally found in people's guts, especially in those of breastfed infants (who have natural protection against many diseases). Most often, the bacteria come from two groups, Lactobacillus or Bifidobacterium. Within each group, there are different species (for example, Lactobacillus acidophilus and Bifidobacterium bifidus), and within each species, different strains (or varieties). A few common probiotics, such as Saccharomyces boulardii, are yeasts, which are different from bacteria.

Some probiotic foods date back to ancient times, such as fermented foods and cultured milk products. Interest in probiotics in general has been growing; Americans' spending on probiotic supplements, for example, nearly tripled from 1994 to 2003.