Probiotics in pediatric gastrointestinal disorders.

Probiotics have been defined most recently as living microorganisms which, upon ingestion in certain numbers, exact health benefits beyond inherent general nutrition. They have been a part of human nutrition for centuries, but in recent years they have been more closely studied for their potential to improve health and treat disease. This review of probiotics is not extensive, highlighting the most recent reviews and well controlled clinical studies in both animals and humans. The safety issues are also discussed as well as potential mechanisms of action. The importance of studying each probiotic bacterium individually in each condition where a health benefit is claimed is highlighted by Lactobacillus GG, the most widely studied probiotic which has proven benefit in reducing the severity and duration of viral diarrhea but no benefit against bacterial diarrhea.