Imagine you’re at a baseball game and decide to add some sauerkraut to your hotdog. Or perhaps you’re rushing between meetings and grab a yogurt to tide you over until lunch. Maybe you’re unwinding after a long week with a little wine and cheese. Each of these tangy products, like sauerkraut and kombucha, is made using fermentation and contains live bacteria that can enhance your health.

Fermented foods like sauerkraut, yogurt, and other dairy products are rich in probiotics—beneficial bacteria that support gut health. These live bacteria can improve digestion, boost the immune system, and even contribute to better mental health. By incorporating fermented foods into your diet, you can enjoy delicious flavors while promoting overall well-being.

Fermented foods and your health

Your gut is teeming with healthy bacteria, creating a unique microbiome that some researchers refer to as our body’s “second brain”. Our other brain is the enteric nervous system which controls our entire gastrointestinal system.

Weighing only 2.2 pounds, it’s a bacterial ecosystem swirling around our intestines, brimming with flora, bacteria, archaea, and yes, even viruses. Our hardworking microbiome helps us digest our food, boost our immune system, and allow our bodies to absorb much-needed vitamins from food.

When we don’t have the right balance of gut microbes that meet our body’s specific needs, then we are more prone to chronic disease, from gastrointestinal issues to neurological, cardiovascular, and respiratory illnesses.

The Journal of Experimental Medicine reports increasing gut probiotics can help improve gastrointestinal conditions like diarrhea, inflammatory bowel disease (IBS), leaky gut syndrome, and liver disease. Scientists also point to the increase in probiotics that can help other conditions, such as neurological, cardiovascular, and respiratory illnesses; and even boost mental health and prevent obesity.

Fermented foods with live cultures are like a multiplier for microbiomes. They have been shown to help us increase the amount of “good bacteria” and probiotic material (12 strains of bacteria grown together) in our gut. When a fermented food with live cultures hits your belly, it releases healthy bacteria and enzymes that make the flora in your digestive system more efficient at synthesizing nutrients. We want those probiotics to stay healthy!

Are all probiotics the same?

If we follow the definition laid out by an international panel of experts at the Gut Microbiota for Health World Summit in 2001 and 2014, all probiotics are the same.

A probiotic is a live bacterium that provides health benefits when consumed correctly (though the “right amount” is still under debate). A bacterium is only considered a probiotic if it can offer a health benefit to humans when ingested.

Robert Hutkins, a professor of Food Science at the University of Nebraska-Lincoln, has dedicated his career to studying bacteria in fermented foods and their ability to survive in our gastrointestinal tract.

Hutkins emphasizes the importance of understanding what indeed constitutes a probiotic, especially in the context of fermented foods. Not every fermented food contains probiotics, as is the case with wine, beer, and canned sauerkraut.

According to Hutkins, foods such as yogurt, most cheeses, kimchi, and non-heated sauerkraut contain probiotics that can positively impact your health.

What can be confusing is that you’ve probably also seen other types of digestive-related ‘biotics’.  In conjunction with probiotics, they are important for a healthy life.

Prebiotics feed your beneficial gut bacteria. When you eat fiber in a variety of fruits and vegetables, your body turns that into food to feed the beneficial bacteria. But before the prebiotics can turn into food for the much-needed bacteria, a fermentation process turns them into probiotics.

There are also postbiotics, the byproducts resulting from prebiotics feeding  on probiotics.

What to remember is to eat your fruits, vegetables, healthy fiber, and fermented foods to gain the best balance of these bacteria to reduce inflammation and strengthen your immune system and overall well-bring. Your ‘second brain’ in the gut will take care of the rest.

How much fermented food is enough?

The experts behind Harvard Health say there is no guidance or data on how many probiotics to consume in a day, but some experts argue that fermented foods shouldn’t be singled out but included in an overall healthy diet.

Lori Zanini, a spokeswoman for the American Academy of Nutrition and Dietetics, says about two to three servings a day of fermented foods should suffice. But, like anything, too much of a good thing isn’t always so good. Experts warn too many fermented foods in your diet could cause gas, bloating, and other gastrointestinal issues.

Sharon Flynn is the author of “Ferment for Good: Ancient Foods for the Modern Gut” and is considered one of Australia’s leading experts on fermented food. She says, like anything, it is possible to overdo it on fermented foods. But, Flynn notes, “You’re more in danger of having poor health from not including these things in your diet than you are from including them.”

The fermentation process

Food growers and producers have long recognized the benefits and popularity of fermented foods in live cultures.

They’re found in almost every culture and cuisine. Historians have even found signs of the fermentation process in food dating back to 7000 BC – making it likely this process has been around as long as humans.

Before refrigeration, fermentation would be one of the only ways to preserve food. If you lived in ancient or medieval times, fermented foods were less likely to make you sick. It’s why most people drank beverages like beer or malted water rather than water up until the 1900s.

Fermentation is a metabolic process that takes sugars and converts them into alcohol or acid. It removes energy from carbohydrates without oxygen.

Fermentation is also known as “culturing” – you can watch this 3-minute video to learn more about this process.

Looking beyond yogurt

Today, there is an increasing variety of fermented foods landing an increasing variety of fermented foods land on our grocery shelves every day.

Here’s a list of some uncommon, fermented foods starting to pop up in our local supermarket to support our nutritional goals. And here’s a website exploring the vast array of fermented foods across the globe.

Kombucha

The increasingly popular beverage can now be found on more grocery store shelves. It begins with a base of green and black tea. Sugar is added to the brewed tea and white vinegar or previously made kombucha for an acidic base.

Brewing kombucha also requires a SCOBY, short for “symbiotic colony of bacteria and yeast.” And don’t worry too much about the sugar used for the fermentation process; most of it is burned off by the time the product gets to the shelf, but check the labels to make sure extra sugar wasn’t added at the end process.

Check out how to make kombucha tea at home.

Kefir

Another item now regularly found on grocery stores shelves in America. Kefir is teeming with probiotics and good bacteria that can make your gut sing. It’s a drinkable yogurt but tangier and higher in probiotics than what’s traditionally found in supermarkets.

It’s fermented by taking kefir cultures ,adding them to a milk product, and letting it ferment for a day. Watch for the sugar content in some brands, though.

Try to make homemade Kefir with this recipe.

Tempeh

Tempeh is a soy-based product that tends to be popular with vegans and vegetarians because it has vitamin B12. It is also a complete protein with all nine essential amino acids needed for healthy bones and bodies.

Check out this marinated peanut tempeh recipe.

Miso

Miso is another culinary delight from Japan but more common in the United States than natto. Like natto, it’s made with boiled soybeans, but instead of being fermented using rice straw, it’s combined with molded rice and salt.

Here’s a recipe for Easy Miso Salmon.

Kimchi

Korean cooks use kimchi in almost every meal. Kimchi, unlike other fermented foods, can be made in different ways. It usually contains a comb of some vegetable (often cabbage), garlic, ginger, chilies, and fish sauce.

The most famous dish is known as Kimchi Jjigae (or Spicy Kimchi Stew); you can find the recipe here.