8 Fermented Foods To Add to Your Diet for a Healthy Gut (2025)

Eating fermented foods can help maintain a healthy gut. Fermented foods are either made with or contain live, active bacteria, such as sauerkraut, kombucha, tempeh, and yogurt. Bacteria or yeast break down the natural sugars in foods. This breakdown yields new compounds like alcohol, carbon dioxide, and lactic acid. Fermentation influences the flavor, texture, and nutrition of certain foods and beverages.

Having a diverse array of helpful bacteria in your intestinal tract supports digestion. These bacteria have been shown to improve mood, regulate blood sugar, lower allergy risk, and support immune function.

People have consumed sauerkraut across cultures for centuries, and it's a source of live, active cultures, as long as it has not been pasteurized. Pasteurized sauerkraut lacks these beneficial microbes since heating kills the bacteria. Sauerkraut with live cultures is typically refrigerated, not shelf-stable. It contains vitamins C and K and boasts anti-inflammatory properties. Cabbage provides sulforaphane, or a compound that may have anti-cancer effects.

While sauerkraut may improve gut health for some, not everyone tolerates it well. Fermentable carbohydrates like mannitol in sauerkraut made from white cabbage can worsen irritable bowel syndrome (IBS) symptoms. It's best to start with a small amount, like 1 tablespoon, and see how you feel.

2. Kombucha

Kombucha is a carbonated, fermented beverage made from tea, sugar, and a symbiotic culture of bacteria and yeast (SCOBY). The SCOBY converts sugars into alcohol and acids, which creates kombucha's tangy flavor. It contains antioxidants from tea and phytochemicals, but studies on its gut health benefits are limited. There are varying nutrient levels in different brands.

Choosing kombucha over soda can be helpful, but it contains added sugars. Consider mixing kombucha with seltzer if you are watching your sugar intake. Kombucha also contains trace amounts of alcohol, with an alcohol by volume (ABV) content as low as 0.5%.

A staple of Korean cuisine, kimchi is another form of fermented cabbage. This side dish is typically made from more ingredients than sauerkraut. Common combinations include napa cabbage, radish, salt, water, fish or soy sauce, garlic, onions, ginger, and red pepper.

Kimchi is rich in fiber and helpful bacterial species like Lactobacilli. It also contains compounds with antioxidant, cholesterol-lowering, and immune-enhancing properties. This unique combination may allow kimchi to help protect against cancer.

4. Tempeh

Similar to tofu, tempeh is a plant-based protein made from fermented soybeans. Tempeh is typically pasteurized and cooked before consumption, so it's not likely to retain active cultures. It still contains antioxidants and paraprobiotics (inactivated microbial cells). These compounds may boost energy, support immune function, enhance muscle strength, improve post-workout recovery time, and reduce anxiety.

Tempeh is rich in heart-healthy plant-based protein and fiber. Just 1 cup of tempeh can provide an impressive 34 grams of protein and 6 grams of fiber.

Kefir is a fermented dairy product made by combining kefir "grains" with milk from cows, goats, sheep, or buffalo. These "grains" are a starter culture of bacteria and yeast that act as a fermenting agent. Kefir and other cultured dairy products have probiotic properties, can improve gut microbial diversity, and reduce inflammation.

Kefir may also improve heart health. One study found that participants who drank kefir daily had increased ApoA1 levels compared to those who drank regular milk. ApoA1 is the primary protein found in high-density lipoprotein (HDL) cholesterol. Kefir also contains protein, potassium, and calcium. It's low in lactose, which can make it tolerable for people with lactose intolerance. You can enjoy kefir like yogurt, add it to smoothies, and use it in marinades.

6. Yogurt

Yogurts that contain live, active cultures are a source of gut-friendly probiotics. Unlike other fermented foods, these bacteria can survive transit through the GI tract. Bacteria need to reach the intestine intact to influence gut health.

Yogurt is also a source of high-quality protein, vitamin B12, calcium, phosphorus, and potassium. Regularly including yogurt in your diet may help manage weight, bone health, blood sugar, and blood pressure.

Follow these tips to choose a yogurt:

• Choose an unsweetened yogurt and add fresh fruit to control the sugar content
• Make sure you see "live, active cultures" in the ingredients list
• Opt for Greek yogurt or Icelandic Skyr yogurt for a higher protein content

Natto and miso are both made from fermented soybeans. These two ingredients are fermented using different bacterial strains. Natto consists of whole fermented soybeans, while miso is a smooth paste made from fermented soybeans.Both have been shown to improve gut, heart, and immune health.

In Japanese cooking, people traditionally add natto to rice dishes and soups or use it to sautée vegetables. You can use miso paste as a seasoning: It lends a powerful umami flavor to many dishes.

8. Apple Cider Vinegar

Apple cider vinegar (ACV) is fermented apple juice high in acetic acid, which is a byproduct of fermentation. Many ACVs undergo pasteurization and filtering, which remove or inactivate the microbes. The cloudy "mother" at the bottom contains natural microbes and is found in raw, unfiltered, unpasteurized ACV.

Some evidence suggests that drinking ACV before meals can prevent blood sugar spikes and lower cholesterol. Try using it in homemade dressings over salads. The combination with fiber may stabilize blood sugar.

There are no official recommendations for how often to eat fermented foods. Regularly including them may improve gut health and reduce inflammation. One study found that eating six servings of fermented foods daily for 10 weeks reduced inflammation and increased gut microbiome diversity compared to those who only increased fiber intake. Try adding one fermented food daily, like kefir at breakfast, kombucha with lunch, or sauerkraut in a grain bowl at dinner.

How To Make Them at Home

You will need sterilized glass jars, salt, a cloth napkin or cheesecloth, and whatever ingredients you intend to ferment. Here are general steps for making fermented vegetables at home:

1. Combine prepared vegetables with salt. Squeeze and mix thoroughly to allow the vegetables' natural liquids to release. You may have to repeat this step multiple times to get enough brine.
2. Mix in your desired herbs and spices.
3. Add the vegetables and brine to a sterilized glass jar. The vegetables should be completely submerged in liquid. Close the jar tightly, then set it aside to be stored at room temperature.
4. You may see bubbles start to form in the jar. You can gently release the lid to let the gases out once a day.
5. How long you allow your vegetables to ferment will depend on the temperature at which they are kept and your preferred flavor profile. This could be anywhere from three days to one month. The longer they ferment, the more tangy they will taste.
6. Store the vegetables in the refrigerator once they ferment, where they can stay good in the fridge for months.

Common side effects of eating fermented foods can include digestive symptoms like bloating and gas in people who are sensitive. Not washing hands or vegetables or not using sterilized jars can increase the risk of harmful microbes. Incorrect storage can also heighten the risk of foodborne illness.

Fermented foods may pose risks for those with histamine intolerance, migraines, or those taking MAOI medications. Consult a healthcare provider to confirm whether fermented foods are safe for you.

Fermented vs. Probiotic Foods

People often use the terms "fermented" and "probiotic" interchangeably, but they are not synonyms. Fermented ingredients are produced with bacteria or yeast and undergo chemical changes. Probiotics are live bacteria or yeast that may offer benefits when you consume them as a supplement or in food.

Some fermented foods contain active bacteria but have not been confirmed to act as probiotics. For a fermented food to be accurately labeled as a probiotic, it must be proven safe, have strain-specific benefits, and contain enough microbes to deliver these benefits. Based on these guidelines, all the foods listed above are fermented, but not all are probiotics.

Fermented foods include sauerkraut, kombucha, tempeh, and yogurt. Regularly including fermented foods in your diet can diversify helpful gut bacteria and offer a range of health benefits. Most fermented foods contain compounds that help fight inflammation and important vitamins and minerals. Start slowly by incorporating one to two servings daily to assess your tolerance.