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13 Fermented Foods for a Healthy Gut and Overall Health

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Fermented foods - Dr. Axe

Whether you realize it or not, fermentation is a process that’s used to produce some of the world’s favorite foods and beverages. Examples of fermented foods include things like wine, beer, yogurt, certain aged cheeses, and even chocolate and coffee. One of the most popular fermented foods globally is yogurt, which has been consumed in certain parts of the world for thousands of years.

Throughout history, fermenting foods gave our ancestors the option of prolonging the freshness of grains, vegetables and milk that were available to them during different seasons. Today, you can make a large batch of fermented foods, such as sauerkraut or yogurt, to have ready to eat in your refrigerator that should last a relatively long time.

What are the benefits of fermented foods? According to a large body of evidence, eating fermented (or “cultured”) foods is the most convenient way to obtain a daily dose of beneficial probiotic bacteria.

Some of the many ways these foods support overall health include by improving digestion and cognitive function, boosting immunity, helping treat irritable bowel disease, providing minerals that build bone density, helping fight allergies, and killing harmful yeast and microbes.


Top 13 Fermented Foods

Below is a list of some of the best fermented foods to include in your diet:

1. Kefir

Kefir is a fermented milk product (made from cow, goat or sheep’s milk) that tastes like a drinkable yogurt. Kefir benefits include providing high levels of vitamin B12, calcium, magnesium, vitamin K2, biotin, folate, enzymes and probiotics.

Kefir has been consumed for well over 3,000 years; the term kefir was started in Russia and Turkey and means “feeling good.”

2. Kombucha

Kombucha is a fermented drink made of black tea and sugar (from various sources like cane sugar, fruit or honey). It contains a colony of bacteria and yeast that is responsible for initiating the fermentation process once combined with sugar.

Do fermented foods like kombucha contain alcohol? Kombucha has trace amounts of alcohol but too little to cause intoxication or even to be noticeable. Other fermented foods, such as yogurt or fermented veggies, typically do not have any alcohol at all.

3. Sauerkraut

Sauerkraut is one of the oldest traditional foods, with very long roots in German, Russian and Chinese cuisine, dating back 2,000 years or more. Sauerkraut means “sour cabbage” in German, although the Germans weren’t actually the first to make sauerkraut (it’s believed the Chinese were).

Made from fermented green or red cabbage, sauerkraut is high in fiber, vitamin A, vitamin C, vitamin K and B vitamins. It’s also a great source of iron, copper, calcium, sodium, manganese and magnesium.

Is store-bought sauerkraut fermented? Not always, especially the canned/processed kind. Real, traditional, fermented sauerkraut needs to be refrigerated, is usually stored in glass jars and will say that it is fermented on the package/label.

4. Pickles

Didn’t think that pickles had probiotics? Fermented pickles contain a ton vitamins and minerals, plus antioxidants and gut-friendly probiotic bacteria.

Are store-bought pickles fermented? Not usually. Most store-bought pickles are made with vinegar and cucumbers, and although this makes the pickles taste sour, this doesn’t lead to natural fermentation. Fermented pickles should be made with cucumbers and brine (salt + water).

What is the best brand of pickles if you want probiotics? When choosing a jar of pickles, look for “lactic acid fermented pickles” made by a manufacturer that uses organic products and brine, refrigerates the pickles, and states that the pickles have been fermented. If you can find a local maker, such as at a farmers market, you’ll get some of the best probiotics for your health.

5. Miso

Miso is created by fermenting soybeans, barley or brown rice with koji, a type of fungus. It’s a traditional Japanese ingredient in recipes including miso soup. It’s been a staple in Chinese and Japanese diets for approximately 2,500 years.

6. Tempeh

Another beneficial fermented food made with soybeans is tempeh, a product that is created by combining soybeans with a tempeh starter (which is a mix of live mold). When it sits for a day or two, it becomes a dense, cake-like product that contains both probiotics and a hefty dose of protein too. Tempeh is similar to tofu but not as spongy and more “grainy.”

7. Natto

Natto is a popular food in Japan consisting of fermented soybeans. It is sometimes even eaten for breakfast in Japan and commonly combined with soy sauce, karashi mustard and Japanese bunching onion. After fermentation it develops a strong smell, deep flavor and sticky, slimy texture that not everyone who is new to natto appreciates.

8. Kimchi

Kimchi is a traditional fermented Korean dish that is made from vegetables, including cabbage, plus spices like ginger, garlic and pepper, and other seasoning. It’s often added to Korean recipes like rice bowls, ramen or bibimbap. It’s considered a Korean delicacy that dates back to the seventh century.

9. Raw Cheese

Raw milk cheeses are made with milk that hasn’t been pasteurized. Goat milk, sheep milk and A2 cows soft cheeses are particularly high in probiotics, including thermophillus, bifudus, bulgaricus and acidophilus.

 In order to find real fermented/aged cheeses, read the ingredient label and look for cheese that has NOT been pasteurized. The label should indicate that the cheese is raw and has been aged for six months or more.

10. Yogurt

Is fermented milk the same as yogurt? Essentially, yes. Yogurt and kefir are unique dairy products because they are highly available and one of the top probiotic foods that many people eat regularly. Probiotic yogurt is now the most consumed fermented dairy product in the United States and many other industrialized nations too.

It’s recommend when buying yogurt to look for three things: first, that it comes from goat or sheep milk if you have trouble digesting cow’s milk; second, that it’s made from the milk of animals that have been grass-fed; and third, that it’s organic.

11. Apple Cider Vinegar

Apple cider vinegar that is raw and contains “the mother” is fermented and does contain some probiotics. It also contains certain types of acids like acetic acid, which supports the function of probiotics and prebiotics in your gut. However, most vinegars available in the supermarket do not contain probiotics.

You can add one tablespoon of apple cider vinegar to a drink twice a day. Before breakfast and lunch or breakfast and dinner, add one tablespoon of apple cider vinegar in your meal, and then start consuming more fermented vegetables like sauerkraut and kimchi or drinking kvass to really boost probiotic levels.

12. Kvass

Kvass is a traditional fermented beverage having a similar taste to beer. Much like kombucha, it goes through a fermentation process and and contains probiotics. It’s made from stale, sourdough rye bread and is considered a non-alcoholic beverage because it contains only around 0.5 percent to 1.0 percent alcohol. The longer it ferments, the more susceptible it is to becoming more alcoholic.

If you’ve never tasted kvass, it has a tangy, earthy, salty flavor and can be an acquired taste. Sometimes it is brewed with flavors from fruits (such as raisins and strawberries) and herbs (such as mint) to make it more appealing.

13. Sourdough Bread

Certain traditionally-made breads, such as real sourdough bread, are fermented, but they don’t contain probiotics. Fermentation helps make nutrients found in the grains more available for absorption and reduces antinutrient content that may make digestion difficult.

Fermented foods - Dr. Axe

How Fermentation Works and Traditional Uses

What are fermented foods exactly? When a food is fermented, it means that it’s left to sit and steep until the sugars and carbs that the food naturally contains interact with bacteria, yeast and microbes to change the chemical structure of the food.

The definition of fermentation is “the chemical breakdown of a substance by bacteria, yeasts, or other microorganisms, typically involving effervescence and the giving off of heat.” The process of fermentation converts compounds, such as a carbohydrate, including vegetables and sugar, to carbon dioxide and alcohol to an organic acid.

The fermentation of foods such as milk and vegetables is also a great way to preserve them for a longer period of time and to make their nutrients more bioavailable (absorbable).

How Is Yogurt Fermented, and How Are Fermented Veggies Made?

According to the Milk Facts website, yogurt is made with a starter culture that ferments lactose (milk sugar) and turns it into lactic acid, which is partially responsible for yogurt’s tangy flavor. Lactic acid decreases pH of milk, causes it to clot and thicken, and gives it a smooth texture.

After fermentation, yogurt contains the characteristic bacterial cultures called Lactobacillus bulgaricus and Streptococcus thermophilusLactobacillus bulgaricus and Streptococcus thermophilus are the only two cultures required by law to be present in yogurt.

Kefir and yogurt are made in a similar way, but the two are a bit different because kefir is made at room temperature with continuous use of kefir grains, which contain a variety of bacteria and yeast. Kefir contains a larger range of bacteria, in addition to containing yeasts, and is more tart/sour then yogurt.

Most fermented vegetables are cultured via the process of lactic acid fermentation (or lacto fermentation) which occurs when veggies are chopped and salted. Fermented veggies contain high acidity and low pH that usually make them shelf-safe and safe to consume for longer than fresh vegetables.

Many fermented vegetables are also made with additional ingredients like coriander, garlic, ginger and red pepper, which also offer various health benefits. The exact microbial counts found in fermented veggies depends on the nutrient status of the fresh produce used and varies with seasons, maturity stage, environmental humidity, temperature and the use of pesticides, among other factors.

Health Benefits

Today we often hear about the benefits of consuming fermented foods for gut health, and there’s good reason why.

The consumption of fermented, probiotic foods has many positive effects on not only the digestive system, but basically the whole body. The microbes that we obtain from eating these foods help create a protective lining in the intestines and shield against pathogenic factors, such as salmonella and E.coli.

Fermented foods’ nutrition is also important for increasing antibodies and building a stronger immune system; plus, they regulate the appetite and reduce sugar and refined carb cravings. In fact, eating cultured/probiotic foods can help treat candida gut.

Another benefit is that lacto-fermentation enhances the nutrient content of foods and makes the minerals in cultured foods more readily available. Bacteria in fermented foods also produce vitamins and enzymes that are beneficial for digestion/gut health.

A study published in the Journal of Applied Microbiology states, “Recent scientific investigation has supported the important role of probiotics as a part of a healthy diet for human as well as for animals and may be an avenue to provide a safe, cost effective, and ‘natural’ approach that adds a barrier against microbial infection.”

Believe it or not, there’s now even evidence that fermented foods reduce social anxiety. Recent research spearheaded by the University of Maryland School of Social Work found a link between social anxiety disorder and the gut health.

A big part of our emotions seem to be influenced by the nerves in our gut (our enteric nervous system). It appears that microbiota influence the gut-brain communication, mood control and behaviors. In animal studies, depression has been found to be linked to the interplay of the brain and gut health, and people with chronic fatigue syndrome have also been found to benefit from probiotic consumption.

Below are benefits of eating some of the most common fermented foods:

  • Yogurt — Yogurt intake has been found to be associated with better overall diet quality, healthier metabolic profiles and healthier blood pressure.
  • Kombucha — After being fermented, kombucha becomes carbonated and contains vinegar, B vitamins, enzymes, probiotics and a high concentration of acid (acetic, gluconic and lactic).
  • SauerkrautStudies suggest that sauerkraut has a variety of beneficial effects on human health; it can help boost digestive health, aid in circulation, fight inflammation, strengthen bones and reduce cholesterol levels.
  • Pickles — Pickles alone can help address the all-too-common vitamin K deficiency, as one small pickle contains 18 percent of your daily value of this fat-soluble vitamin, which plays an important role in bone and heart health.
  • Kimchi — Kimchi is known to improve cardiovascular and digestive health and has high levels of antioxidants that may help reduce the risk of serious health conditions, such as cancer, diabetes, obesity and gastric ulcers. A report published in Bioactive Foods in Health Promotion states, “Health functionality of kimchi, based upon our research and that of others, includes anticancer, antioxidative, antiobesity, anti-constipation, serum cholesterol and lipid-controlling, antidiabetic, and immune-boosting effects.”
  • Natto — It contains the extremely powerful probiotic bacillus subtilis, which has been proven to support the immune system and cardiovascular health. It also enhances the digestion of vitamin K2. In addition to these natto benefits, it contains a powerful anti-inflammatory enzyme called nattokinase that has been shown to potentially have cancer-fighting effects.
  • Miso — Miso has anti-aging properties and can help to maintain healthy skin. It also boosts the immune system, may help lower the risk of certain types of cancer, improves bone health and promotes a healthy nervous system.
  • Tempeh — Tempeh contains high levels of vitamins B5, B6, B3 and B2. Eating it regularly may help reduce cholesterol, increase bone density, reduce menopausal symptoms, promote muscle recovery and has roughly the same protein content as meat.

How to Get Fermented Foods in Your Diet

If you’re new to fermented foods, start by having about a half a cup per day and build up gradually from there. This gives your gut time to adjust to the presence of new bacteria. It’s best to eat a variety of different fermented foods, since each one offers different beneficial bacteria.

Where can you buy fermented foods? These days, you can find them at just about any supermarket. Yogurt is widely available, and other fermented foods like kefir, sauerkraut and kimchi are becoming easier to find. Look for fermented foods in health food stores, large supermarkets and at your local farmers market.

How to Make Fermented Foods:

What foods can you ferment at home? The list is long: many vegetables, grains, soybeans, milk, etc. For example, fermented vegetables you can prepare at home include cabbage, carrots, green beans, turnips, radishes and beetroots.

Here is a basic homemade fermented foods recipes using vegetables you may already have on hand (note that you can also refer to this homemade sauerkraut recipe):

  • Fermenting vegetables is relatively easy, and you only need a jar with some salt and water. Salt and water combined make brine, which aids in the fermentation process.
  • Use a regular wide-mouth mason jar. Prepare the vegetables for fermenting by grating, shredding, chopping, slicing or leaving them whole.
  • Once the vegetables have been prepared and placed in the chosen jar, cover them with brine and weigh them down so they don’t float up. Thoroughly sprinkle the salt onto the veggies and massage them a bit. Add any other ingredients, such as spices. If there’s not enough liquid released, add more salted water (brine). There should be a little room at the top of the jar since bubbles will form during fermentation. Make sure the lid is on tightly while the veggies ferment.
  • Most veggies need two to seven days to ferment. The longer you leave them to ferment, the stronger the taste will get. Once the vegetables are finished culturing, move them to cold storage.

Other fermented food recipes may require the use of kefir grains, whey, yeast or a starter culture, depending on the exact recipe and your personal taste (you can refer to the Cultures for Health website for specific recommendations).

Fermented Food Recipes:

Here are ideas for adding fermented foods to your diet:

  • Add sauerkraut and pickles to your favorite burger slider recipes.
  • Try adding yogurt or kefir to these healthy smoothie recipes.
  • Make a salad dressing with apple cider vinegar, raw honey, olive oil and dijon mustard, and toss on one of your favorite salads. You can add cultured veggies like radish, sauerkraut, etc., to salads as well.
  • Make a meatless dinner by subbing tempeh for meat in this Buddha bowl recipe.
  • Try this simple miso soup recipe with mushrooms.
  • Add kimchi to a veggie stir-fry or homemade ramen bowl.
  • Sip on kombucha, combined with some seltzer if you’d like, instead of soda or other sweetened drinks.

Fermented Foods on Keto:

No matter what type of diet you follow, it’s a good idea to consume probiotic foods regularly. If you’re following the ketogenic diet, it’s highly recommended that you regularly include cultured vegetables, such as sauerkraut and kimchi, in your meals. These provide probiotics along with essential vitamins and minerals, and they can supply salt, which is needed on the keto diet to balance water loss.

A small amount of full-fat (ideally raw) dairy products, such as unsweetened yogurt or kefir, may also be consumed on the keto diet. Just be sure to avoid any product that is sweetened with fruit, sugar, etc. Dairy products should be limited to only “now and then” due to containing natural sugars. Higher fat, aged cheeses have the least carbs and can be consumed in quantities of about 1/4 cup per day. Limit yogurt/kefir to about 1/2 cup per day or less.

You can also use apple cider vinegar in dressings, marinades, etc., or mixed with water.

Fermented Foods in Traditional Chinese Medicine and Ayurveda:

A healthy Ayurvedic diet includes fermented foods, such as yogurt, amasai and miso. Many different seasonal vegetables may be fermented to prolong how long they are edible, such as asparagus, beets, cabbage, carrots, cilantro, fennel root (anise), garlic, green beans, etc.

Ayurvedic and Indian fermented foods are often combined with anti-inflammatory herbs and spices. These include turmeric, cumin, fennel, ginger, cardamom, coriander, cinnamon, clove, rock salt, mint, black pepper and oregano. Fermented foods are especially encouraged for Vata types, who can benefit from foods that have a natural sour and salty taste, rather than those that are bitter, pungent and astringent.

In Traditional Chinese Medicine, fermented foods are included in the diet to help prevent deficiencies, support the gut and vital organs, and improve detoxification. The stomach and spleen are the two main pathways that TCM practitioners believe are related to Qi (“vital energy”) deficiency, and both of these organs can suffer due to low nutrient intake, use of medications, stress and other factors.

Sauerkraut, kimchi, and other fermented/pickled vegetables and fruits, are utilized to help restore the healthy bacterial colonies found within the gastrointestinal tract.  Soy sauce, black beans, radishes and other foods are also commonly fermented in China and used in TCM. These foods make it easier for the gut to allow nutrients to be absorbed during digestion and can build immune deficiencies.

Precautions and Potential Side Effects

Are there any dangers of fermented foods?  While they certainly have lots of benefits to offer, one disadvantage of fermented foods is that when you consume too much, especially too quickly, you may deal with some digestive issues. These can include bloating or diarrhea. Start slowly and experiment with different kinds to find your favorites.

If you have a sensitive digestive system you may want to start off with a smaller amount, like several tablespoons of kefir or one probiotic capsule a day, and work your way up.

For the greatest fermented foods benefits, try to purchase foods that are organic and contain “live and active cultures.” This is better than the label “made with active cultures.” After fermentation, some poor quality products may be heat-treated, which kills off both good and bad bacteria (extending shelf life). Ideally you want to find raw, organic and local products that do not contain lots of sugar or additives.

Final Thoughts

  • The meaning of fermented foods is those that are left to sit and steep until the sugars and carbs that the food naturally contains interact with bacteria, yeast and microbes. This changes the chemical structure of the food and creates healthy probiotics.
  • What foods are fermented? Some of the most widely available and best fermented foods to include in your diet are: kombucha, yogurt, aged/raw cheeses, sauerkraut, pickles, miso, tempeh, natto and kimchi. Other healthy foods that are fermented include apple cider vinegar, wine, sourdough bread and chocolate.
  • Why are fermented foods good for you? Fermented foods naturally provide us with probiotics, beneficial bacteria that mostly live within our gut/digestive system.
  • Health benefits of fermented foods and probiotics include: improving digestion/gut health, boosting immunity, helping treat GI issues like irritable bowel disease, providing minerals that build bone density, helping fight allergies, supporting heart and metabolic health, and killing harmful yeast and microbes that cause issues like candida.

Read Next: Top 15 Anti-Inflammatory Foods and Anti-Inflammatory Diet

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