You have bacteria living in your gut. Sounds bad, but it's actually good. These are "friendly" bacteria that help keep bad bacteria and yeast from growing in your intestinal tract. They also help make vitamin K and keep your immune system functioning properly.
Normally you have an abundance of friendly bacteria. However, antibiotic therapy, stress, and poor dietary choices may all cause intestinal dysbiosis, which is a bacterial imbalance that results in overgrowth of bad bacteria and yeast.
Dysbiosis has been linked with disorders like yeast infections, irritable bowel syndrome and rheumatoid arthritis. A common cause of dysbiosis is antibiotic therapy. The antibiotics that you take for killing an infection will also kill the healthy bacteria in your digestive tract.
Prebiotics and probiotics can restore the balance of bacteria in your digestive tract.
Probiotics and Prebiotics
Probiotics are beneficial bacteria that can be found in various foods, or you can buy them as dietary supplements. When you consume probiotics, you add these healthy bacteria to your intestinal tract.
Common strains include Lactobacillis and Bifidobacterium families of bacteria.
They're naturally found in fermented foods like sauerkraut and yogurt (more in regular yogurt, less in frozen yogurt). Some foods will have added probiotics as healthy nutritional ingredients, which will be evident on the label.
Prebiotics are non-digestible foods that make their way through our digestive system and help good bacteria grow and flourish. They help feed and keep beneficial bacteria healthy.
Prebiotics mostly come from carbohydrate fibers called oligosaccharides. You don't digest them, so the oligosaccharides remain in the digestive tract where they stimulate the growth of beneficial bacteria. Sources of oligosaccharides include fruits, legumes, and whole grains.
Fructo-oligosaccharides may be taken as a supplement or added to foods.
Probiotics and Children
Probiotics are generally safe for children, however you should speak with your pediatrician before giving them to your kids. They may be beneficial for digestive complaints and diarrhea, but research hasn't clearly indicated any benefits beyond that.
Collins MD, Gibson GR. "Probiotics, prebiotics, and synbiotics: approaches for modulating the microbial ecology of the gut." Am J Clin Nutr. 1999 May;69(5):1052S-1057S.
Lamoureux L, Roy D, Gauthier SF. "Production of oligosaccharides in yogurt containing bifidobacteria and yogurt cultures." J Dairy Sci. 2002 May;85(5):1058-69.
Thomas DW, Greer FR. "Probiotics and prebiotics in pediatrics." Pediatrics. 2010 Dec;126(6):1217-31.