Trillions of bacteria live in your intestines — but don’t be grossed out! Many of them are “good” bacteria that help keep us healthy.
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Think of it like having pets living inside of you. And, as with any pets, you’ve got to feed them. Gail Cresci, PhD, RD, who studies gut bacteria, says a modern Western diet heavy on processed foods can upset the balance of your gut microbiota, which can lead to unpleasant gastrointestinal symptoms.
Fermented foods can help. Dr. Cresci explains a few reasons why bringing back traditional fermented foods, such as fermented sauerkraut or pickles, into your diet is good for optimal health.
Good bacteria help break down complex carbohydrates that you eat. This fermenting and metabolizing process results in other substances that are beneficial to your body, too.
For a diverse gut microbiota, you need plenty of soluble fiber from foods like beans, oats and oranges. Insoluble fiber, which is found in many whole grains, is good for you, but it’s not easily fermented, so it doesn’t really contribute to the diversity of your gut bacteria.
Every day, you swallow pathogenic (disease-causing) bacteria. You don’t always get sick from it, though, because your tiny microscopic helpers take care of it. Good bacteria create acidic fermentation byproducts that lower your intestine’s pH, decreasing the chance that bad bacteria can survive. They also compete for food supply and squatting rights on your intestinal lining. Plus, they secrete antimicrobial proteins that kill off bad bacteria.
Tiny bacteria in your intestine have full-body effects. Research shows a less diverse gut microbiota is associated with many chronic disease, such as obesity, asthma and chronic inflammatory conditions such as inflammatory bowel disease. Research is still ongoing into why this is the case.
Ever had diarrhea or other digestive problems after taking antibiotics? That’s because they wipe out both good and bad bacteria. Eating fermented foods may help restore your gut bacteria to normal. Be sure to eat a diet high in fiber and plant-based foods, which gut microbes flourish on.
Mix and match these gut-healthy foods for optimal benefits.