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.
1. You can’t digest food alone
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.
2. The good bacteria fight the bad — and usually win
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.
3. Your body needs help making certain vitamins
Good bacteria are to thank for synthesizing, or producing, many vitamins your body needs. That list includes vitamins B1, B2, B3, B5, B6, B12 and K.
4. A healthy body needs balance
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.
5. They can help restore your gut health after taking antibiotics
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.
Go for variety
Mix and match these gut-healthy foods for optimal benefits.
- Kombucha: This slightly fizzy fermented tea is a good alternative to soda. Find it in your grocery store’s refrigerated section, or brew your own using just tea, water, sugar and a “mother” or synbiotic colony of bacteria and yeast in 7 to 30 days.
- Pickles: Your best bet is to pick a variety from the grocery store’s refrigerated section. Or, better yet, make your own lacto-fermented pickles with brine (cooled sea salt solution), dill, mustard and coriander seeds, and peppercorns.
- Sauerkraut: Find live versions of this traditional Eastern European staple, which literally translates to “sour cabbage,” in the refrigerator case. Or, if you don’t mind chopping, make your own artisan batches.
- Kimchi: There are hundreds of varieties of the traditional Korean fermented side dish, commonly made from a base of napa cabbage, radish, scallions and spices. Find your favorite version at Asian markets or grocery stores, or experiment with flavors at home.
- Yogurt: Yogurt is made from fermenting milk (or a nondairy alternative) with a starter culture of bacteria. Some commercial varieties also contain additional probiotic bacteria.
- Kefir: This fermented dairy drink is made using kefir grains (a combination of bacteria and yeast). The end result? A slightly fizzy, tangy drink that’s thinner than yogurt. Find it in the dairy case.