| Probiotics are live organisms that, when ingested in adequate amounts, provide a health benefit to the person who consumes them. The most commonly used probiotics are lactobacilli, bifidobacteria and non-disease-causing yeasts such as Saccharomyces boulardii. Products labeled as “probiotics” are now widely available; however some may not contain sufficient live organisms to convey a health benefit due to formulation, storage conditions (consistent cool temperature is recommended) or failure to survive as they pass through the gastrointestinal tract.
Probiotics offer many health benefits:
Probiotics are important in recolonizing the intestine during and after antibiotic use. Preparations containing one or more strains of beneficial bacteria can prevent or lower the risk of antibiotic-associated diarrhea and “traveler’s diarrhea”. Infection of the colon with Clostridium difficile, can occur following antibiotic therapy and lead to a serious complication known as pseudomembranous colitis. Probiotics may prevent the development and recurrence of C. difficile infection. Probiotics may also be used to treat inflammatory bowel disease, irritable bowel syndrome, and food allergy. Evidence is emerging for the effectiveness of probiotics in the prevention of postoperative infections. Potentially preventable conditions range from necrotizing enterocolitis to urogenital infections, skin diseases, respiratory diseases, and dental caries (cavities). Scientists are intrigued by the possibility that probiotics could lower cholesterol and reduce the risk of cancer and kidney stones. Future uses of probiotics may include the treatment of cystic fibrosis and rheumatoid arthritis.
Some experts believe that probiotics should be part of the daily diet, because our immunity is frequently compromised. Allergies, atopic skin diseases like eczema, asthma, autoimmune diseases, and other immune-related conditions are on the rise because:
Probiotics have been clearly shown to boost immunity, especially in subjects with less than adequate immune function such as the elderly. Twice daily supplementation with Bifidobacterium lactis was found in a double-blind trial to significantly enhance various aspects of immune function in a group of healthy elderly people after only six weeks of supplementation. A study published in 2010 suggests that probiotics may lower the risk of common childhood illnesses such as ear infections, strep throat, and colds.
Probiotics secrete enzymes that promote healthy digestion. For example, acidophilus is a source of lactase, the enzyme needed to digest milk sugar, which is lacking in lactose-intolerant people. Probiotics may be helpful in preventing malnutrition, improving calcium absorption, and in relieving constipation. Recent research also suggests that probiotics may decrease Helicobacter pylori infections which are responsible for gastric ulcers, and decrease the risk of certain cancers.
Probiotics may reduce the recurrence of urogenital infections in women. Most cases of bacterial or yeast vaginitis and urinary tract infection arise from contamination with bacteria from the woman’s gastrointestinal tract, as microbes travel the short distance from the anus to the vagina. The more common presence of these pathologic organisms has led to an increase in bacterial vaginitis which in turn has increased the rate of preterm labor and premature births. Regular oral consumption as well as vaginal use of probiotic bacteria may help to prevent bacterial vaginitis.
Yogurt is often promoted or even recommended as a source of probiotics. However, different brands of yogurt can vary greatly in bacterial strains and potency. Some (particularly frozen) yogurts do not contain any live bacteria. “…there’s no evidence that Lactobacillus acidophilus, which is used in many commercial yogurts, has any benefits for diarrhea,” according to Martin Floch, MD, a professor of gastroenterology at Yale University, co-author of Probiotics: A Clinical Guide, and a consultant for the Dannon Company.
Specific probiotic organisms appear to be useful for particular illnesses. Probiotic preparations should say the name of the specific bacteria they contain, as well as how many organisms a single dose provides. The amount of probiotics necessary to replenish the intestine varies according to the extent of microbial depletion and the presence of harmful bacteria. One to two billion colony forming units (CFUs) per day of acidophilus is considered to be the minimum amount for the healthy maintenance of intestinal microflora. Some S. boulardii research has used 500 mg taken four times per day. It seems that, at least for acute infectious diarrhea, higher doses of probiotics given for short courses are more effective than lower doses and are equally safe. Adequate doses of probiotics can be provided as standardized supplements in powder, liquid extract, capsule, or tablet form.
Research continues to report additional benefits of probiotics to prevent and treat illness.
For further reading, see our friends at HealthAmbition.com below in the references for more information.
|Aliment Pharmacol Ther. 2012;35(12):1355-1369.