Fermenting was first used as a means of food preservation, before times of refrigeration and grocery stores. Most of us now associate eating fermented foods with improved gut health, and evidence shows that gut health can play an important role in metabolism, immunity, inflammation, mood, allergies, as well as autoimmune disorders.
Unfortunately, fermented foods have all but disappeared in our newly sterile, overly-processed world of food, and what our current Western-style diet lacks, traditional diets thrive on. In Asia, they consume tempeh and miso, both from fermented soy. In the Caucasus Mountains, it is kefir from fermented milk. In Africa, they enjoy fermented porridge and cassava. In Korea it is Kimchi and in Germany it is Sauerkraut. Does our health suffer when our modern day diet lacks fermented foods? What are the health benefits of fermented foods? Here are my top 9 common gut health foods you have at home.
What Impacts Our Gut Bacteria?
Our gut microbiome is continuously changing; sometimes we can exert some control over it, other times it’s out of our hands. External forces such as medications and climate and internal factors including increasing age and stress can have a negative impact on our gut flora. A diet rich in meat, simple sugars, refined flours, high in fat and low in fibre can also promote the growth of undesirable bacteria. Luckily, encouraging the growth of good bacteria is as simple as consuming a diet high in gut health foods including high fibre foods, rich in legumes, and low in meat and processed foods. Read my top 5 tips for optimal gut health here. Eating fermented foods is a way of introducing more beneficial bacteria into our gut, but is their role limited to just that?
Health Benefits of Consuming Fermented Gut Health Foods
The fermentation process itself, whether or not live-active cultures are alive, confers some health benefits. Bacteria will die if heated above 115 degrees Fahrenheit but sourdough bread continues to be advantageous. It is not solely reliant on if bacteria cultures are alive in the consumed food, and in this, we can understand that fermented foods are not important solely for gut health. The Art of Fermentation by Sandor Ellix Katz breaks down the benefits of fermentation for us;
- Pre-Digestion – What fermentation is is the digestive action of bacteria and fungus. When they ‘eat’ the sugar in the food it is metabolized into a basic form that our body can use more efficiently. Minerals become more bioavailable, and certain difficult-to-digest compounds are broken down. Soy protein can be broken down into amino acids that are easier to digest. In milk, the lactose is broken down into lactic acid, which is why those with a lactose-intolerance can generally tolerate yogurts.
- Nutritional Enhancement – During the digestive action of bacteria and fungus, increased levels of thiamin (B1), riboflavin (B2), niacin (B3) appear at higher quantities than in the raw unfermented food. Fermentation also increases the availability of the essential amino acid lysine in cereal grains including in properly fermented sourdough, compared with pure yeast fermentations. Fermentation of cabbage can increases the Vitamin C in Sauerkraut, as well as indole-3-carbinol an important detoxifying compound.
- Detoxification – Fermentation has been used to remove a variety or toxic compounds in traditional foods including cyanide in ‘bitter’ cassava tubers. Fermentation also helps to reduce phytate content in nuts and legumes which can improve the availability of minerals including zinc. See Zinc Deficiency in Vegans and Vegetarians.
- Live Bacteria Cultures – The above three health benefits are not dependent on whether the fermented food is cooked or not. Uncooked foods fermented by lactic acid bacteria will contain the benefits of lactic acid bacteria which can reach our digestive tract, surviving the acidic environment of our stomach (particularly when buffered by food). In our gut they work in complex ways we are only beginning to understand – this can include elaborate interactions with our intestinal microbiotia and the mucosal cell linings of our digestive tract which can provoke beneficial immune responses.
What Does The Science Say About Fermented Gut Health Foods
We know that fermented foods introduce good bacteria to our gut flora which can help strengthen our gut wall again invading pathogens, influencing our immune system. In practice, fermented foods are also an important tool in helping to manage symptoms of irritable bowel disease (IBS) or inflammatory bowel disorders.
Many miraculous claims have been made on behalf of fermented foods, and it is always important to approach these claims with a level of skepticism. I do not think that a daily dose of apple cider vinegar is going to cure diabetes. The potential improvement of overall health does not necessarily ensure any particular outcome, and we need to think critically about any outlandish health claims that promise ever-lasting health. Fermented foods are part of the picture of optimal health and well-being, as is exercise, a healthy balanced diet, stress management and good sleeping habits. Research is ongoing on the effects of live-active cultures on health, but from history, we can see that they have an important role to play.
9 Common Fermented Gut Health Foods You Have At Home
So how do you increase your fermented food consumption if you’re not so into Kimchi, and the only time you’ll eat Sauerkraut is on a dirty hotdog? It is likely that you have a few fermented foods already taking up space in your fridge or pantry.
- Miso – Miso is made from fermenting soy and barley or rice. Soy-free versions exist and are made from fermenting chickpeas. Miso soup is the most common way of enjoying miso (see Japanese Miso and Soba Noodle Soup). Be sure to not let the miso boil, and instead add it to hot water to ensure the bacteria aren’t killed off. I love miso in salad dressings such as this Japanese Salad Bowls with Miso Tahini Dressing.
- Yogurt – The bacteria in yogurt help to break down the lactose making the food more digestible. The diversity of the strains can be limited in conventional yogurt, as well as the amount of live-active culture (unless you are purchasing one that specifically indicates it contains live-active cultures). Kefir, a fermented yogurt drink, contains a higher amount of live-active cultures than yogurt. Try this tasty yogurt coleslaw for a healthy twist on this common dish.
- Sourdough – Traditional fermented sourdough is easier to digest, and those who have difficulty digesting wheat may find that sourdough is a better option through the partial breakdown of gluten. While we won’t get any active benefits of the live cultures once the bread is baked, sourdough – alongside tempeh – is a good example of how fermentation can help pre-digest food, allowing for easier access to nutrients.
- Tempeh – The fermentation of the soybeans provides a pre-digestion of the protein into easier to digest amino acids, and helps break down phytate which allows for more bioavailability of minerals. The tempeh we have access to likely does not contain any available vitamin B12, rather inactive analogs so vegans should not rely on it as a source.
- Apple Cider Vinegar – True vinegar is naturally fermented and will contain a mother culture; you should be able to see it at the bottom of the bottle as a cloudy, stringy culture. Make sure you purchase apple cider vinegar that is unpasteurised to obtain any health benefits. Here is a delicious dressing based on apple cider vinegar.
- Kombucha – This newer ferment is made from fermenting sweet tea with a SCOBY or Symbiotic Culture of Bacteria or Yeast. It’s sudden popularity has not necessarily been backed up by research. Like any ferment it contains unique metabolic by-products and living bacterial cultures that may or may not agree with you. Start with small amounts and see how it tastes and feels for you.
- Cider – Fermenting fruit, as well as grains, tubers, sugar or honey into alcohol, will offer some wild yeast. Pasteurised versions will not contain any live-active cultures.
- Pickles – Fermented pickles are available and will contain the beneficial live-active cultures as long as they are not pasteurised. These are going to be found in the refrigeration section of the grocery store and not on the shelves. You can also find fermented mustards, relishes here as well as unpasteurised kimchi and sauerkraut.
- Soy Sauce – The fermentation of soy into soy sauce is said to be one of the most complex of fermented foods, involving three district groups of organisms including Aspergillus, lactic acid bacteria and yeasts. Soy sauce is made from fermenting soy and wheat, whereas tamari is solely soy (resulting in a less complex flavour). Make sure you purchase organic soy sauce to avoid any genetically-modified soy, and a high-quality one made exclusively by the fermentation process.
The leap into the world of fermentation may seem scary at first, but if you have some miso in your fridge try adding it to a salad dressing or a pesto. Use yogurt in place of sour cream in soups. Swap your tofu for tempeh once in a while. To ensure you are getting maximum benefits from fermented foods, try including at least one fermented food in your diet per day. This could be as easy as having a bowl of yogurt for breakfast!
References for Fermented Foods Health Benefits & 9 Gut Health Foods In Your Home
The Art of Fermentation – Sandor Ellix Katz
Rachel Dickens, The Conscious Dietitian, is a Registered Dietitian and Certified Diabetes Educator. She graduated with her Masters in Nutrition and Dietetics in 2010 from Griffith University. She strives to provide evidence-based nutrition information with a focus on plant-based nutrition, and share some of her favourite seasonal recipes and sustainable eating tips.