After a winter filled with commercials warning about germs' ill effects, it's easy to forget that many bacteria are beneficial to health. More than 400 strains of friendly flora, or probiotics, work with our bodies to fight off disease in a variety of ways. In fact, good bacteria secrete antibacterial substances, competing with the bad "bugs" to help us withstand these diseases. Probiotics also help balance the immune system, fighting allergies and reducing the risk of cancer. While they populate our gastrointestinal tract, the benefits of friendly bacteria also travel to the respiratory system and the urogenital tract.
Important for the Very Young
Babies first encounter bacteria when they pass through the birth canal-unless they're delivered by Cesarean section. Breast milk contains probiotics, critical since infants' immune systems are still undeveloped. "For babies who can't be breastfed, supplementation with probiotics has been found to establish better intestinal health," says Earl Mindell, RPh, PhD. "If you would like to try this with your own child, do so with the guidance of your pediatrician," he adds.
A good deal of research on probiotics focuses on their benefits for diarrhea, especially in children. An extensively investigated strain, Lactobacillus rhamnosus shortened the duration of diarrhea due to rotavirus in one randomized, double-blind, placebo-controlled trial. Other clinical trials find that
Lactobacillus GG and Saccharomyces boulardii significantly lessen the incidence of diarrhea caused by antibiotic drugs.
Probiotics have proved effective in treating young children with moderate-to-severe dermatitis. Swedish research finds differences in microflora between healthy and allergic infants. Intestinal microflora may be "the major external driving force in the maturation of the immune system after birth," this study explains.
Experimental research suggests that beneficial bacteria exert antiallergic effects on immune and intestinal epithelial cells, protecting the gut's defense barrier. Probiotics appear to reduce intestinal inflammation, which can cause tiny holes in the intestinal wall, allowing food particles to enter the bloodstream. Since the immune system works to rid the body of these particles, friendly bacteria prevent immune reactivity and allergies.
Not surprisingly, probiotics are useful for inflammatory bowel disease (IBD), supporting the internal ecosystems of those with Crohn's disease, irritable bowel syndrome (IBS), and ulcerative colitis. And the role of good bacteria extends to healthy individuals, too.
Without probiotics, digestion, absorption, and detoxification cannot proceed normally. This explains why antibiotics usually cause digestive problems, since these drugs kill off good as well as bad bacteria. Many probiotics increase the acidity of the GI tract, protecting against pathogens and yeasts. Candida albicans yeasts in the digestive tract and mucous membranes quickly grow and spread when the levels of good bacteria fall, setting the stage for severe yeast overgrowth throughout the body and compromising immunity.
Friendly flora also protect against H. pylori bacteria, implicated in stomach ulcers and cancer. Not only do probiotics themselves fight infection by killing off bad bacteria, but they also enhance the activity of white blood cells (which attack pathogens) and support cytokine production (which helps cells communicate effectively). Animal research suggests that friendly bacteria help inhibit the growth of cancer caused by toxic chemicals and may even protect against colon cancer.
Beneficial bacteria manufacture a host of nutrients in the body: amino acids, antioxidants, B complex vitamins, vitamin K, and short-chain fatty acids. Bacterial cultures used to ferment foods make nutrients more bioavailable in the body and can help people with lactose intolerance enjoy yogurt and other fermented dairy products.
A number of factors can cause the level of friendly flora in the body to decline: diets high in refined foods, chlorinated water, antacids and other acid-lowering drugs, intestinal flu, internal cleansing, some health screenings (such as a colonoscopy), synthetic estrogens (in birth control pills and hormone replacement therapy), antibiotic and steroid drugs, and stress. You may need probiotic supplements to restore your supply of friendly flora.
Nutritionist Betty Kamen, PhD, calls live culture probiotics (available in a yogurt-like mix or nondairy medium) the "gold standard." But she also recommends dry capsule products for a mix of different species. "Ideally, the probiotic supplement you choose should contain L. acidophilus and/or other Lactobacillus strains and strains of Bifidobacteria," says Dr. Earl Mindell. "Probiotics are safe even in doses far greater than anyone would intentionally take," he adds. However, anyone with severe immune dysfunction or any life-threatening disease should use probiotics only under professional supervision.
Selected Sources "Clinical Effects of Probiotics…in Very Young Children with Atopic Dermatitis" by S. L. Prescott et al., Clin Exp Allergy, 12/05 "Evidence of Probiotics in Prevention of Allergy and Asthma" by B. Bjorksten, Curr Drug Targets Inflamm Allergy, 10/05 "Irritable Bowel Syndrome and Probiotics: From Rationale to Clinical Use" by E. F. Verdu and S. M. Collins, Curr Opin Gastroenterol, 11/05 "The Mechanism of Action of Probiotics" by Sonia Michail, MD, Practical Gastroenterology, 5/05 "Probiotics as Functional Foods" by D. C. Lin, Nutr Clin Pract, 12/03 "Treatment of Acute Infectious Diarrhea in Infants and Children with a Mixture of Three Lactobacillus rhamnosus Strains…" by H. Szymanski et al., Aliment Pharmacol Ther, 1/06 User's Guide to Probiotics by Earl Mindell, RPh, PhD ($5.95, Basic Health, 2004)
Probiotics are living microorganisms that contain beneficial bacteria or yeasts that support metabolism, nutrient absorption and the immune system. Often recommended by doctors to counteract gastrointestinal and other side effects of antibiotics, probiotics help restore the body?s balance of gut flora.
The word is getting out about helpful germs and bacteria, known as acidophilus.
Study after study from many of the most prestigious universities in the country support and advance the concept that probiotics are as important and basic to our health as a balanced diet and exercise.