By Rick Ansorge

Probiotics are live microorganisms – usually bacteria – that are similar to the “good” or “friendly” bacteria naturally found in the human gut. Probiotics are available in foods such as yogurt, fermented and unfermented milk, miso, tempeh, and some juices and soy beverages; and in dietary supplements packaged as capsules, tablets, and powders.

Probiotics usually come from two groups of bacteria: Lactobacillus and Bifidobacterium. But a few common probiotics also contain yeasts such as Saccharomyces boulardii.
Friendly bacteria are important to the proper development of the immune system, protecting against unfriendly microorganisms that cause disease, and also assisting in the digestion and absorption of food and nutrients. But the mix of friendly and unfriendly microorganisms varies from person to person.

This mix can be upset by antibiotics, which kill both friendly and unfriendly bacteria in the gut, resulting in side effects such as gas, cramping, and diarrhea. So people who take antibiotics often attempt to counterbalance these effects with probiotic foods or supplements. Other people use probiotic foods and supplements to counteract symptoms of lactose intolerance, which result from the lack of an enzyme needed to digest a sugar in milk products.

The bacterial balancing act also can be disrupted by disease-causing bacteria, yeasts, fungi, and parasites. So researchers also investigating whether or not probiotics can either halt these unfriendly microorganisms, of suppress their growth in conditions such as:

• Infectious diarrhea.
• Irritable bowel syndrome.
• Inflammatory bowel disease (e.g., ulcerative colitis and Crohn's disease.
• Infection with Helicobacter pylori (H. pylori), a bacterium that causes most ulcers and many types of chronic stomach inflammation.
• Tooth decay and periodontal disease.
• Vaginal infections.
• Stomach and respiratory infections that affect children in daycare.
• Skin infections.

In 2005, a conference convened by the National Center for Complementary and Alternative Medicine concluded that there is encouraging evidence that specific probiotics formulations may be effective in:

• Treating diarrhea, especially for diarrhea from rotavirus.
• Preventing and treating infections of the urinary tract or female genital tract.
• Treating irritable bowel syndrome.
• Reducing the recurrence of bladder cancer.
• Shortening the length of an intestinal infection caused by a bacterium called Clostridium difficile.
• Preventing and treating pouchitis (a condition that can follow surgery to remove the colon).
• Preventing and managing atopic dermatitis (eczema) in children.

Other research suggests that probiotics may prevent or reduce the severity of colds and flu, and reduce missed work days due to respiratory or gastrointestinal illness.

Most people can safely add probiotics foods and supplements to their diet, with only mild possible side effects such as gas and bloating. But more research is needed on the possible side effects in young children, older people, and those with compromised immune systems. Ask your doctor if probiotics are right for you.  Also make sure he or she knows all the medications and supplements you are currently taking to check for possible interactions.  

SCEDULE A SCREENING

Sources
http://nccam.nih.gov/health/probiotics/index.htm
http://www.mayoclinic.com/print/probiotics/AN00389/METHOD=print