Gut Health 101: Top Prebiotic and Probiotic Foods
What you need to know about keeping your gut microbiome in top shape, including foods and supplements that nourish gut health.
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How important is gut health? 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 directly with the digestive system, but 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 its microbiome. According to Josh Axe, DC, a Nashville-based doctor of natural medicine and author of Eat Dirt, “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 friendly bacteria or probiotics-help absorb or produce vitamins, while others eliminate pathogens or support health in other ways.
Care and Feeding of Pre- and Probiotics
“Most people are severely deficient in probiotics,” says Axe. Why? Because these friendly bugs are killed off by antibiotics in medications, meat and poultry raised on factory farms, and hand sanitizers, as well as by pesticides in food and beverages, fluoride and chlorine in drinking water, and other toxins. For this reason, Axe says, we all need to eat probiotic-rich, fermented foods and to take probiotic supplements.
Probiotics come in different species (the first part of the name of each one) and strains, and we need a variety for optimal gut health. 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.
Consider the Source
Although there are many species of probiotics, says Axe, they come from two main sources:
- Soil-based probiotics: 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. In supplements, the Bacillus species is soil-based. Soil-based probiotics pass through the gut, eliminating harmful organisms, but they don’t take up residence, so we need an ongoing supply. They are more resilient to stomach acid than other types.
- Food-based probiotics: Most other species, including Lactobacillus and Bifidobacteria, are found in fermented foods.
One other type of probiotic, the Saccharomyces species, is a 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
1. For general health maintenance: Take 50 billion colony forming units (CFUs) daily of a supplement with a combination of species, with food. Some products also include prebiotic fibers, such as acacia gum, FOS (fructooligosaccharides), or inulin. Refrigerated products should be kept in the fridge, and even shelf-stable ones may last longer if refrigerated.
2. If you’re taking antibiotics, you need to increase your intake of probiotics considerably. Take probiotics several times daily, at least 2 hours apart from antibiotics, and aim for 100–500 billion CFUs per day.
3. If you suffer from chemical or food sensitivities, start with a product that contains only soil-based organisms (Bacillus species), as these are less likely to trigger a reaction.
Top Probiotic Foods for Gut Health
- Yogurt and kefir (dairy- or plant-based)
- Sauerkraut
- Kimchi
- Kvass (a fermented beet drink)
- Natto
- Miso
- Kombucha
- Raw cheese from goat’s or sheep’s milk
- Any other naturally fermented food
Did You Know? Sour foods and drinks, such as apple cider vinegar or lemon water, create a hospitable pH for probiotics to thrive.
Top Prebiotic Foods List
- Asparagus
- Onions
- Garlic
- Leeks
- Raw honey
- Chicory root
- Jicama
- Barely ripe plantains and bananas
- Sprouted whole grains
- Seeds
- Berries
Different probiotics strains and 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.
