“Ew. Why would I eat bacteria?” My undergraduate nutrition students reacted to the suggestion that eating probiotics, or friendly bacteria, might confer health benefits. Waivering on germ phobic, Americans lag behind Europeans and Asians in understanding the importance of good bacteria for digestive health and wellbeing. But a walk past supermarket dairy cases exploding with probiotic products -- like Dannon's Activia yogurt, Stonyfield Farms Shift energy drink, Kraft's LiveActive cheese snacks -- suggests that good-for-you gut bugs are beginning to enjoy a spot on America's plate.

Few of us realize we're a walking petri dish. Billions of bacteria - some 400 different types -- live in our gut. Some are helpful. Others cause problems. Probiotic means “pro-life.” In contrast to antibiotics (meaning “against life”) which kill harmful germs, probiotics are foods or supplements with tiny living organisms (mostly bacteria) that are thought to yield health benefits, like aiding digestion, boosting immunity, curbing allergies, and crowding out harmful germs like salmonella or Candida. The bacterial “balancing act” can be thrown-off in several ways: with antibiotics that kill both good and bad bacteria, diets high in meat, fat, sugar, or alcohol that create a hostile digestive environment, illness, stress or exposure to environmental toxins. Eating probiotics may help restore balance.

Health Benefits
Microbes have been essential to food and alcohol fermentation for thousands of years. A century ago, Russian zoologist Elie Metchnikoff first documented health benefits of bacteria, noting that Bulgarians who ate fermented dairy (like yogurt) lived longer. He hypothesized that lactic acid-producing bacteria prevented “fouling” of the colon. Today, about 20 different species of bacteria are considered probiotics. Most common are lactobacilli (like L. acidophilus - mainly inhabit small intestine) and bifidobacteria (like B. Bifidum - mainly in colon).

With growing threats of antibiotic resistance, it's important to consider ways to prevent infections and strengthen our immunity. Compelling scientific evidence of healing benefits of probiotics is emerging, albeit gaps remain. Each type of bacteria is unique, yielding health effects that cannot necessarily be generalized to all probiotic bacteria. The strongest evidence supports probiotics to treat diarrhea and constipation, including rotaviris infections in children (using Lactobacillus GG, L.reuteri, B.bifidum, S. thermophilus), Clostridium difficile-induced diarrhea in elderly, and antibiotic-induced and traveler's diarrhea. L.acidophilus and bifidus milk have helped relieve constipation in elderly. L. salivarious and L. johnsonii may inhibit H. pylori bacteria associated with stomach ulcers. Lactobacilli bacteria in fermented dairy products, like yogurt, aid dairy digestion in people with lactose intolerance by delivering some lactase enzyme to the intestines. Lactobacilli also reduce recurrence of vaginal yeast and bacterial infections, possibly by acidifying genital areas. As it ferments in foods like yogurt or cheese, bifidobacteria nourishes by synthesizing some vitamins (especially B-complex), acidifying the gut which enhances absorption of minerals like calcium and magnesium, and releasing enzymes that digest protein and fats. Other benefits? Certain probiotics may boost immune response, curb allergies and baby eczema, lower cholesterol and blood pressure, protect from colon or bladder cancer, and even ward off tooth decay. Getting a daily dose of probiotics simply makes good health sense.

Getting Good-For-You Gut Bugs
* Eat cultured foods with live probiotics often to replenish good bacteria to your gut. Most are dairy products, like yogurt, kefir (fermented milk), buttermilk, acidophilus milk, some cottage cheese. Unfortunately, heat from pasteurization kills bacteria. For yogurt you can look for “Live Active Cultures” label which ensures some live bacteria are added back (but not always true “probiotic” strains). Choose organic products which may have higher potency and are free of antibiotics, pesticides, or growth hormones. Unfortunately, foods are rarely labeled with amounts or type of bacteria; consumers can try contacting the company. Recently some non-dairy probiotic foods have hit US shelves, like Kashi Vive cereal and Attune Foods wellness bars. You can also get beneficial bugs from fermented foods like sauerkraut, vinegar, pickles, olives, apple cider vinegar, miso, and tempeh.
* “Feed” your good bugs by eating lots of their favorite plant foods (also called “prebiotics”) so they'll stick around and multiply. They thrive on natural fibrous treats (like inulin and fructooligosaccharides or FOS) from fresh fruits, vegetables, whole grains and legumes especially Jerusalem artichokes, chicory, bananas, tomatoes, asparagus, garlic, onions, dark leafy greens, legumes like lentils, barley, oats. Some commercial products (Horizon and Stonyfield yogurts) combine prebiotics with probiotics (called “symbiotics”), but introduce slowly since 5-10 gram doses of FOS may cause gas/bloating at first.
* Consider over-the-counter probiotic supplements after antibiotics, or to remedy specific conditions like diarrhea, yeast infection, etc. These often include a mixture of beneficial bacteria. Capsules are preferred because they have greater viability than loose powders, liquids, chewables. Some, like Enzymatic Therapy Pearls, have special coatings to survive stomach acid and digestive fluids. Freeze drying is common which stabilizes the probiotics so they are dormant until moistened in the digestive tract. A daily dose of 1 to 10 billion “colonizing forming units” (CFUs) is recommended. Unfortunately, maintaining potency through the shelf life is a problem and most supplements will have less than the label claims by the time you eat them. Follow storage directions, usually refrigerating.
* Note: Since health benefits are strain-specific, check out www.usprobiotics.org for supplements and food products with probiotics tailored to aid a specific condition. Also, probiotics have a long history of use and are generally safe, but immuno-compromised people and those taking medicines (interactions are possible) should check with their doctor before using.

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