In 2002, a joint statement published by the Food and Agriculture Organization (FAO) and the World Health Organization (WHO) defined probiotics as “live microorganisms which, when administered in adequate amounts, confer a health benefit on the host.” Most commercially available probiotic products are strains of Bifidobacterium or Lactobacillus bacteria or Saccharomyces yeast. Lactobacillus caseii rhamnous GG (Whew! Fortunately abbreviated as LGG) is the most extensively studied bacterial probiotic.
Prebiotics are substances (such as certain carbohydrate sugars) that are not digested, and when they reach the large intestine, they stimulate the growth of beneficial bacteria. Breast milk has a large supply of healthy prebiotic carbohydrates. Symbiotics are a combination of probiotics and prebiotics.
The Gut–Where Probiotics work
When a baby is born, there are no bacteria in the colon. However, shortly after birth, bacteria start living (colonizing) in the large intestine. Breastfed babies have different bacteria (flora) than formula fed babies, which experts hypothesize may contribute to the fewer diarrheal illnesses experienced by breastfed babies. Formula fed babies tend to colonize more harmful strains of bacteria as normal residents of the colon. In certain circumstances, the harmful bacteria can cause problems.
Probiotics show promising positive effects in certain gastrointestinal and allergic diseases. Probiotics and Diarrheal Illnesses Probiotics show benefit in people who have a mild to moderate case of a stomach virus. They also help prevent antibiotic-associated diarrhea (AAD). Various over the counter Saccharomyces and Lactobacilli supplements are available to treat these types of diarrhea. Evidence suggests that probiotics need to be taken early in the course of diarrhea in order to be effective.
Bifidobacterium has been shown to have some effect in preventing relapses of ulcerative colitis in adults.
Probiotics and Colic
Lactobacillus reuteri has been shown to be highly effective in treating colic in babies. In fact, Lactobacillus reuteri worked better than the anti-gas drops that are the most often used medication to treat infantile colic.
There has been a great deal of research on probiotics and allergic illnesses. Studies have shown that LGG given to pregnant women and infants (in breast milk or LGG supplemented formula) may reduce the development or severity of eczema related to cow’s milk allergy in children.
Every spring, hay fever suffers search for a new way to treat their runny noses, sinus congestion and itchy eyes. Unfortunately, the evidence to date suggests that probiotics do not help prevent or treat seasonal allergic rhinitis or environmental allergies such as to pet dander.
Remember, probiotics are live bacteria, and they should be taken with the same precautions as any medicine or supplement. The risks and benefits of ingesting live bacterial or yeast cultures should be weighed carefully. Caution must be exercised with the use of probiotics in immunocompromised patients (patients with cancer or immune system defects). Consult your physician before using any probiotic.
Probiotics are not regulated by FDA
So why are probiotics more effective than say, plain old yogurt? Probiotics contain much larger amount of bacteria (over 108 microorganisms per gram of supplement) than yogurt. Remember, though, probiotics are not regulated by the Food and Drug Administration (FDA), and studies have shown significant variability in the number of colony forming units available in various probiotic formulations.
Reference: Food and Agriculture Organization, World Health Organization. The Food and Agriculture Organization of the United Nations and the World Health Organization Joint FAO/WHO expert consultation on evaluation of health and nutritional properties of probiotics in food including powder milk with live lactic acid bacteria, FAO/WHO Report No. 10-1-2001.
This article is for informational purposes only and should not substitute for medical advice from your healthcare provider. The author is not providing personal medical opinion, diagnosis or course of treatment. Do not delay or substitute this information for medical treatment.
Last updated August 22, 2009 by Dr. Vee