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As many as 70 million Americans suffer from digestive diseases, and many others have symptoms that may stem from an unhealthy gut, from joint pain, bad moods, and skin problems to frequent colds and flu, bacterial infections, autoimmune diseases, or simply bloating after meals. In many cases, it’s difficult to connect indications with the digestive system. Nevertheless, that’s where up to 80 percent of the immune system lives.
Why is the gut so powerful? It isn’t the gut itself but rather, the microbiome. If you’ve heard about it a zillion times but are still mystified, not to worry. Josh Axe, DC, a Nashville, Tenn.-based doctor of natural medicine and author of Eat Dirt, has a simple explanation: “The microbiome really operates like an organ, only it’s not made of tissue in your body—it’s made up of trillions of microorganisms.”
Just as your stomach knows to secrete digestive juices when you eat, the microbiome, located in the intestines, has its own intelligence. “It’s sort of your own body’s ecosystem of microbes that have different functions, keeping your body in balance,” says Axe. Some microbes—aka probiotics or friendly bacteria—help absorb or produce vitamins while others eliminate pathogens or support health in other ways.
Care and Feeding of Probiotics
“Most people are severely deficient in probiotics,” says Axe. They’re killed off by antibiotics in medications, meat and poultry raised on factory farms, and hand sanitizers; pesticides in food and beverages; fluoride and chlorine in drinking water; and other toxins. We all need to eat probiotic-rich, fermented foods, he says, and take supplements.
Probiotics come in different species (the first part of the name of each one) and strains, and we need a variety. Like other living organisms, they need food—in the form of prebiotics. To keep track of these terms, “pre” comes before “pro,” and probiotic organisms must eat prebiotics before they can survive.
Two Main Types of Probiotics
Although there are many species, says Axe, in nature and in supplements, probiotics come from two main sources:
Found on plant foods that have not been radiated or sterilized. For example, if we ate locally-grown, organic carrots and just washed them gently, rather than scrubbing off the top layer, we would ingest these organisms, as our ancestors did. In supplements, the bacillus species is soil-based. Soil-based probiotics pass through the gut, eliminating harmful organisms, but don’t take up residence, so we need an ongoing supply. They are more resilient to stomach acid than other types.
Most other species, including lactobacillus and bifidobacterium, are found in fermented foods.
One other type, the saccharomyces species, comes from yeast. To restore and maintain a healthy balance, which helps the body heal itself and stay in good shape, Axe recommends getting a variety of all three types.
How to Benefit from Probiotics and Prebiotics
For health maintenance:Take 50 billion colony forming units (CFUs) daily of a supplement with a combination of species, with or without food. Some products also include prebiotic fibers, such as acacia gum, FOS (fructooligosaccharides), or inulin. Refrigerated products should be kept in the fridge, and shelf-stable ones may last longer if refrigerated. Always eat foods that are rich in probiotics and prebiotics.
If you’re taking antibiotics, take probiotics several times daily, at least 2 hours apart from antibiotics. Aim for 100 to 500 billion CFUs per day.
If you suffer from food or chemical sensitivities, start with a product that contains only soil-based organisms (bacillus species), as these are less likely to trigger a reaction.
Probiotic and Prebiotic Benefits
Although we all need a variety of probiotics, says Axe, these are some specific benefits of individual ones:
- Bacillus subtilis: Helps fight autoimmune disease and leaky gut.
- Saccharomyces boulardii: Helps treat acne and inflammatory bowel diseases (IBS).
- Bifidobacterium infantis: Alleviates IBS symptoms, diarrhea, and constipation.
- Bacillus coagulans: Improves nutrient absorption and reduces inflammation and symptoms of arthritis.
- Bifidobacterium bifidum: Supports production of vitamins in the gut and prevents diarrhea.
- Lactobacillus casei: Helps fight infections.
- Lactobacillus acidophilus: Relieves gas and bloating and reduces lactose intolerance.
Top Probiotic Foods
- Yogurt and kefir (dairy or plant-based)
- Kvass (a fermented beet drink)
- Raw cheese from goat’s or sheep’s milk
- Any other naturally fermented food
Top Prebiotic Foods
- Raw honey
- Chicory root
- Barely ripe plantains and bananas
- Sprouted whole grains