You may be hearing a lot about "fermented foods" right now, as they are being featured more often in the media and by healthcare practitioners. Despite all of this increased attention, a good sceptic may be asking: are these supposed "superfoods" actually any good for you, or is it all hype? Let's dig in and figure it out!
What are Fermented Foods?
Fermented foods are simply food products that have undergone changes through microbial action (aka fermentation). This is also known as "culturing," as microbes are sometimes referred to as cultures. These changes will include texture, taste, acidity, smell, and even nutrient content. Microbes like bacteria and yeast, either added to or naturally present in/on the food, will essentially start to digest parts of the food and transform it in the process.
For this transformation to happen, the conditions need to be just right for different types of fermentation, such as temperature, humidity or salinity, and different microbes thrive in different environments. The end result is a food that is similar, yet different, than before it underwent this microbial action. Think of cabbage turning into sauerkraut or milk into yogurt; you can certainly still recognize the original food, but the product of fermentation is different and unique.
What are Examples of Fermented Foods?
Fermenting foods has been a practice all over the world, for somewhere between 10,000-20,000 years. This was one of the original ways to preserve food, along with drying and freezing , that people learned to do in order to extend the life of their harvest. And, as we will see later on, this practice also had other benefits besides food preservation.
Some examples of different fermented foods from around the world (that you can still enjoy today) are:
This is just a snippet of the fermented foods available, and if you haven't tried any of the foods on the above list, I encourage you to try at least one asap! There are also many common foods we consume that are the product of fermentation, that we may not even realize are fermented, such as cheese, vinegar, beer, wine, cured meats, coffee and chocolate. All of these items undergo fermentation before arriving in their delicious, well-known forms found in our homes.
Many foods that were once traditionally fermented, but may no longer undergo this process due to modern food processing. One example is bread, which was traditionally leavened with sourdough yeast cultures, but is now made with commercial yeast. This is also true of most pickles nowadays, as the majority at the store are preserved with a vinegar brine rather than fermented in a salt brine as would have happened before canning.
Do Fermented Foods Have Any Benefits?
While it is easy (and wise) to be skeptical of foods promoted via tv and magazines, I can confidently say that yes, fermented foods really are good for you! It is important to remember that these are traditional foods and not just a food fad; as mentioned above, these have been around for millennia, and were prized for their nutritional value long before they were featured on blogs.
Certainly, fermented foods have made a comeback in the last few years, but they are not new, nor did they ever really go away--we are just more aware of them due to the increasing popularity of ancestral diets and focus on gut health. There is lots of evidence to back up the claim that fermented foods have many health benefits.
1. Fermented Foods Can be Probiotic (and Prebiotic!)
Many fermented foods contain beneficial bacteria and yeasts (probiotics), which are the very microbes that facilitate the fermentation process. An example of this would be the Lactobacilli that turn cabbage into sauerkraut, which are probiotics. These bacteria give the process its name, lacto-fermentation, which is a term you may see used, and you can be asured it has nothing to do with lactose, but rather the Lactobacilli cultures.
Fermented foods can contain anywhere from millions to trillions of microbes in just a single teaspoon. Though we know many of the microbes involved in various fermented foods, there are still many strains that are yet undiscovered. Microbes like these confer numerous benefits to those consuming these foods, including supporting digestive health, decreasing inflammation and playing a role in a healthy immune system. As these microbes pass through the digestive tract, they offer benefit to the eater.
For some people, using a targeted, strain-specific probiotic supplement is still necessary for healing their gut, but for many, simply adding in more of these fermented foods can help to improve digestion and more. Plus, supplements will not necessarily offer the other benefits of fermented foods...and I am all about food first!
Though many are, not all fermented foods are probiotic, nor are all probiotic foods fermented--if fermented foods undergo heat processing (like canning, baking, or some beer and wine-making) they are no longer probiotic, as the microbes cannot survive those extreme conditions. So, if a fermented food has not undergone heat processing, it is most likely still probiotic. Another example is vinegar, which is fermented but not probiotic due to the acetic acid content, though it is still a beneficial, healthy food to consume.
There are some "functional foods" on the market that are not fermented, but have had probiotic cultures added to them after processing, such as in sodas and protein powders. I am not against these foods, and they can be a good source of probiotics, but they may not be fermented, so they will not necessarily have all of the benefits of fermented foods.
Fermented vegetables and beans like kimchi or tempeh will also contain prebiotic fiber, while fermented dairy like yogurt and kefir supply galacto-oligosaccharides that acts as prebiotics as well. Prebiotics are key in gut health, as they feed and support a healthy microbiome, making foods like these a double dose of digestive support.
2. Fermentation Increases Digestibility of Foods
The microbial action undergone by fermented foods can not only make them probiotic, but can also make the end product easier to digest than the original food. This can be seen in dairy fermentation, where the Lactobacilli digest the lactose in milk, leaving the fermented milk product (kefir, yogurt, or cheese), lower in lactose and, thus, easier to digest for those who are lactose intolerant.
Many who cannot eat commercial bread find that sourdough bread, which has undergone several hours of fermentation before baking, is more tolerable due to the breakdown of starches and gluten proteins during fermentation. The "souring" process used to make sourdough also lowers the glycemic index and FODMAP content of the bread, while increasing the resistant starch content, giving it even more potential for health benefits, especially for those with digestive issues.
Fermenting foods can also help reduce the content of some "anti-nutrients" in foods like grains, vegetables and beans. These are compounds like phytates and lectins that inhibit digestion and absorption of nutrients, such as zinc or magnesium. These can also cause digestive distress in those with sensitive guts. By fermenting these foods, the amount of many anti-nutrients can be decreased, therefore increasing the digestibility and availability of nutrients in the foods.
3. Fermentation Increases the Vitamin Content of Foods
By fermenting foods as a means of preservation rather than canning, you are preserving the nutritional content in these foods, as they will not undergo heat and pressure treatment.
However, fermentation not only can help prevent nutrient loss, but it also can increase the nutritional content of the finished product. One example of this is with vitamin K2. This vitamin is important because it signals calcium into the bones and teeth, and away from soft tissues like blood vessels. K2 is key in improving bone and teeth health, as well as promoting heart, brain, and kidney health. Luckily, we can increase the K2 in our diets through more fermented foods. Pastured animal foods like milk, eggs and liver are wonderful sources of vitamin K2, but fermentation increases the K2 content of foods even more, as it can be produced by bacteria. This makes foods like grass-fed cheese an excellent K2 source. Other fermented foods like natto, a soybean ferment from Japan, are great sources as well.
During fermentation, bacteria can also create vitamin B12, making foods like kim chi or tempeh sources of this vitamin that it would not have been prior to fermentation. Though animal foods like meat are the best way to get adequate B12 in the diet, including fermented foods in an omnivorous diet can help get even more B12, and can supplement vegetarian diets with bacteria-produced B12.
4. Fermented Foods Contain Post-Biotics
Postbiotic may be a new term for some; it sounds similar to pre- and probiotics, and they are related in a way. Postbiotics are metabolic byproducts created by bacteria during fermentation, which themselves have health benefits beyond those of the bacteria themselves. This is another example of how fermented foods have health-promoting properties that the original food would not have contained prior to fermentation.
Examples of postbiotics found in fermented foods are short chain fatty acids (which promote colonic health), polysaccharides (which can act as a prebiotic), enzymes, and organic acids to help promote digestive health, decrease inflammation and more. This is another "-biotic" that is becoming available as a supplement, as some may get health benefits from these metabolites who cannot tolerate probiotic supplements or fermented foods, but I encourage starting with food whenever possible and trying supplements if not well tolerated.
5. Fermented Foods Taste Good!
This may not seem like a "benefit," but enjoying your food is an important part of mindful eating and we all deserve to love our food. Fermented foods have such different flavors than any other foods, adding variety to your plate and a pop of flavor to your meal.
Most ferments, especially those that are lacto-fermented, have sour as their dominant flavor due to the presence of lactic acid-producing bacteria (LAB's). The sour taste is actually beneficial to digestion as it stimulates salivation--saliva contains digestive enyzmes--and secretions throughout the digestive tract. In healing traditions like Traditional Chinese Medicine and Ayurveda, the sour flavor is associated with balancing properties such as stimulating the liver (TCM) and lungs (Ayurveda).
Sour, acidic foods can support digestion in the upper GI tract for those with low stomach acid and can be helpful for nausea, including during pregnancy. However, for those with ulcers, gastritis or excess stomach acid, consuming large amounts of acidic ferments may be contraindicated; sticking with lower-acid ferments or limiting serving sizes would be wise, and consider adding in a probiotic to supplement until you can tolerate these foods.
Some Easy Recipes and What to Look for When Buying Fermented Foods
I encourage making things yourself whenever possible, so you know the exact ingredients and processes that went in to making your food. If you are interested in recipes to get started, here are a few from my blog so you can try your hand at DIY fermentation:
Perhaps you are nervous getting started with the DIY-route, or there are ferments that you want to try but don't have the equipment to make at home, or you just want to taste something first to see if you like it before committing to making it at home. In these cases, store-bought ferments can be a great option. However, not all ferments on the store shelves are created equally, and you need to carefully read the labels to get traditionally fermented foods.
Here are a few criteria to look for when purchasing fermented foods at the store:
Beginner Tips for Eating Fermented Foods
If you are totally new to eating fermented foods, my best advice is to start slowly. Try one new ferment at a time, starting with just 1 or 2 teaspoons per day, and gradually increasing your intake as tolerated. There is no "upper limit" for fermented foods, but you really only need a small amount to get benefits from them. As you try more ferments, aim to increase the diversity, not just the amount, of fermented foods you eat on a regular basis.
Our general rule is to have something fermented at each meal, as often as possible; this could look like a spoonful of sauerkraut on a pastured hot dog or brat, a kefir smoothie with breakfast, a sprinkle of kim chi on eggs, a glass of kombucha with lunch, or a miso dressing with dinner.
Even small children should be adding in ferments on a daily basis--they particularly love yogurt, pickles and cheese, and some even like kombucha! Whatever ferments you like, incorporate them into as many meals (or even snacks and desserts!) that you can, even just a small amount daily.
Contraindications for Adding Fermented Foods
Some new to ferments may find that they get some gas, bloating, stool changes, or GI upset when adding them in; small amounts of these symptoms may be normal, but if you experience significant gut changes after adding in small amounts of fermented foods, you may need to do some gut healing before making ferments a regular part of your diet.
As mentioned above, those with gastritis or related issues may need to moderate their intake of ferments and avoid higher-acid items like vinegar until healing has taken place.
Folks with gut dysbiosis (such as SIBO/SIFO), leaky gut, IBS, IBD and other gut conditions may find that they do not tolerate fermented foods. In these cases, going through a gut-healing protocol that helps to address underlying infections and overgrowth, decrease gut inflammation, balance the microbiome, and repair the gut lining, is an important to step before being able to enjoy ferments, and of course, will help improve overall health.
For some conditions, probiotic supplements may work better rather than starting with fermented foods as a source of beneficial microbes, as they may be better tolerated.
Want to Know More?
Want to learn to make your own fermented foods or need more support with healing your gut? Reach out!
Visit my website here to learn about upcoming fermentation workshops (including virtual classes!) or find me here to learn more about working with me on your gut healing journey--including signing up for a FREE 15-minute call!
Brine & Broth
I am a gut health-focused nutritionist and online health coach based in Southwest Wisconsin. My recipes and philosophies center around traditional, nutrient-dense foods that support robust gut health.