What to Know About Fermented Foods

Reviewed by Poonam Sachdev on June 22, 2021

Fermentation is a way to preserve certain kinds of foods. Fermented foods and drinks are produced through the controlled growth of “good” bacteria, which preserve the food's nutritional benefits for storage.

In recent years, fermented foods have had a surge in popularity, mainly due to their health perks. 

Fermentation causes bacteria or yeast to change the elements within certain foods and drinks, giving them extra nutritional value. It also gives food distinctive flavors and textures. 

There are thousands of examples of foods that are fermented. Some of the most popular ones are:

Many of these foods have been around for thousands of years and are used by different cultures around the world. Dairy products are often fermented to create cultured drinks like kefir, or to make thicker foods like yogurt. Also, many cultures have developed traditional foods that are based on fermented vegetables -- like kimchi, pickles, and sauerkraut -- or soybeans to create miso, tempeh, or natto.

Not only does fermentation allow these foods to be preserved for longer periods of time, but the process also changes their flavor and texture. In recent years, researchers have begun to understand that fermented foods also have a positive impact on people's digestive health.

Your digestive system is full of millions of different beneficial bacteria and other tiny organisms. While the word "bacteria" often makes people think of sickness, research today says it's important to have a diverse and healthy gut microbiome, which is the complex collection of microbes that live in your digestive tract. These beneficial bacteria and microorganisms help fine-tune your body’s defenses (immune system) and protect against inflammation, which may lead to conditions ranging from obesity and diabetes to neurodegenerative diseases. 

Other research is beginning to show that fermented foods may be linked to benefits like these:

  • Anti-carcinogenic: works against the processes that can lead to cancer
  • Anti-microbial: slows or stops the growth of potentially dangerous microbes
  • Anti-allergenic: prevents or relieves the symptoms of an allergic reaction
  • Anti-fungal: slows or stops the growth of fungus
  • Anti-inflammatory: lowers inflammation throughout the body 
  • Anti-diabetic: helps control the level of blood sugar
  • Anti-atherosclerotic: prevents or counteracts atherosclerosis, a kind of heart disease
  • Anti-anxiety: helps ease the symptoms of anxiety

Scientists don't yet have a complete understanding of all the ways that the human microbiome influences our overall health. There is evidence that gut health is connected to a wide variety of other body functions, ranging from blood pressure and heart health to mental health and conditions like depression and anxiety. Studies are ongoing, and more important discoveries continue to be made.

Look for fermented food choices in the refrigerated section of the grocery store. These are more likely to have healthy amounts of live organisms compared to fermented foods on the shelves. Avoid cooking these foods over high heat, because that may kill the "good bacteria" that gives your gut the full benefits of fermented foods. Instead, add them as a topping or at the end of cooking.

Fermented foods are a healthy part of a diverse diet. They add beneficial bacteria to your digestive system and give you exciting new flavors and textures. With the wide variety of traditional fermented foods from around the world, there is no shortage of tasty recipes to explore, as well as easy ways to work more fermented foods into your diet.

Show Sources


Critical Reviews in Food Science and Nutrition: "Health benefits of fermented foods."

Food & Nutrition: "The History and Health Benefits of Fermented Food."

Harvard Health Publishing: "Fermented foods can add depth to your diet."

Heart Foundation: "Fermented foods: the latest trend."

Kansas State University and the University of Missouri: "Safely Fermenting Food at Home."

Microbiome: "(Dis)Trust your gut: the gut microbiome in age-related inflammation, health, and disease."

Nutrients: "Fermented Foods: Definitions and Characteristics, Impact on the Gut Microbiota and Effects on Gastrointestinal Health and Disease."

University of Massachusetts Medical School Center for Applied Nutrition: "Fermented Foods for Gut Health."

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