What are fermented foods?

Fermented foods are a staple of many different global food cultures, from German and Japanese to Korean and Indian. Historically, fermentation was done out of necessity, to preserve foods and prevent them from spoiling quickly. Virtually any food can be fermented, including vegetables (like cabbage, for kimchi and sauerkraut), milk (in yogurt), tea (in kombucha) and various grains and fruits (for beer and wine). Fermentation is complicated, but in a nutshell, it works like this: Microbes—yeast, bacteria or mold—are introduced to a particular food. They feast on carbohydrates found in the food, breaking down these sugars and starches into either alcohol or into lactic acid or acetic acid. The acidic environment prevents harmful mold and bacteria from growing. This process increases both the number of functional microorganisms (the “good” bacteria) and certain vitamins and minerals in the food, thereby making it more nutritious. By breaking down sugars and starches before we consume them—typically the stomach’s job—it actually makes them easier for us to digest.

7 possible health benefits of fermented foods

There’s been a lot of excitement over the possible health benefits of probiotics, and for good reason: Initial studies do look promising. But a word of caution before diving into a vat of sauerkraut: Most of the studies looking into the benefits of fermented foods have been conducted on cells in a dish or on animals, or used only a small number of human participants. So while much of the research looks good, it’s not conclusive until more high-quality studies are conducted. Additionally, formulations of probiotic supplements can vary widely and aren’t regulated by the Food & Drug Administration. Probiotics may interfere with certain medications, so always share your usage with your physician. Food is a good way to get those probiotics, plus lots of other important nutrients. Here are a few possible ways they may help your health.

1. Improve digestion and GI issues

We’ve heard a lot about how probiotics in fermented foods can be good for our gut microbiome. When there are more bad bacteria than good in our lower intestines, we can suffer from uncomfortable digestive problems, including constipation, diarrhea and bloating. Adding more good bacteria to the mix can bring our guts back in balance and keep everything running smoothly. Probiotics have long been recommended when taking antibiotics to reduce the risk of diarrhea.

2. Strengthen the immune system

Our guts and our immune systems are intertwined, as 70% of our immune system resides in our digestive tract. Improving the microbiome can reduce chronic inflammation, obesity and other conditions that stress the immune system by making it think it’s under constant attack from an “invader.”

3. Build stronger bones

Studies showed probiotics in fermented milk products and moringa leaves improved the foods’ ability to release calcium and the body’s ability to absorb it. Besides calcium, many of the other vitamins and minerals needed for bone health are present in lots of fermented foods. Research has also found kefir increased bone mass in rats.

4. Boost mental health

Research has found people with anxiety and depression often have gut problems, elevated levels of inflammation and immune-system dysfunction. Probiotics from fermented foods may improve gut issues and make vitamins and minerals, including vitamins B12 and K, more easily absorbed. They may also help synthesize mood-modulating neurotransmitters, like GABA and serotonin.

5. Reduce cardiovascular risk

Increased levels of inflammation, immune dysfunction and unbalanced gut flora are known to be present in cardiovascular diseases, including hypertension and arrhythmia. Research has found a link between healthy gut bacteria and reduced risk of certain cardiovascular diseases.

6. Regulate metabolism and blood sugar

A healthy gut can reduce the risk of obesity and type-2 diabetes, common risk factors for cardiovascular disease. Probiotics have been found to balance the microbiomes and decrease inflammation in people with type-2 diabetes, as their gut flora is different from those who don’t have the disease. Research has foundprobiotic supplementation resulted in weight loss, decreased waist circumference and reduced BMI in overweight or obese adults. Some studies have found probiotics, like those found in fermented foods, can lower fasting blood-sugar levels and improve insulin resistance.

7. Decrease allergy symptoms

Allergies—whether they’re seasonal springtime sniffles, skin conditions like eczema, or reactions to foods—are caused by an overreaction by the immune system. Because most of our immune system is found in the gut, improving the immune system as a whole may be able to quell allergy symptoms. On the flip side, some people have reactions to probiotic-rich foods. Alcohol and fermented foods produce lots of histamines—the chemical that causes itchy, watery eyes, sneezing, and other symptoms.

15 best-fermented foods to try

Want to start incorporating more fermented foods into your diet? Add these to your grocery list:

Kefir: This fermented milk beverage is similar to drinkable yogurt. Fermentation eliminates most of its lactose, making it digestible even for those with lactose intolerance.Kombucha: Made by fermenting tea and sugar with a SCOBY (“symbiotic culture of bacteria and yeast”), the bubbly beverage is widely available in a ton of flavors. You can also make your own at home.Sauerkraut: It means “sour cabbage” in German, which is precisely what the beloved Reuben ingredient and hot-dog topper is—so feel free to add some this tasty fermented food to your next meal.Kimchi: In Korean, “kimchi” can be a catch-all term for any fermented vegetables, though its most well-known formulation is with cabbage.Tempeh: These fermented soybean cakes hail from Java and are a common meat substitute in plant-based diets.Natto: Natto is a traditional Japanese dish made from fermented soybeans and is typically served over rice.Lassi: Although mango may be the most well-known flavor, this fermented Indian yogurt drink comes in many different sweet and even salty varieties.Sourdough bread: Sourdough starter couldn’t be simpler: flour, water and wild yeast found in the flour and air. Fermentation gives the bread its signature tanginess, and may even make it easier to digest for people with gluten sensitivities.Yogurt: Look for three magic words on the label: “live active cultures.” That tells you the yogurt contains strains of probiotics. Some brands are specifically marketed as probiotic yogurts, though they all contain beneficial bacteria if they contain LACs. Non-dairy probiotic yogurt brands include GT’s CocoYo, Nancy’s and Forager Project.Miso: This Japanese staple is made by fermenting soybeans and a type of mold called koji over a span of weeks, months or even years until it turns into a rich, deeply flavored paste.Aged cheeses: Some of your favorite cheeses are fermented, though they’re more commonly known as “aged.” Fermented cheeses have a longer shelf life than non-fermented ones, which spoil more quickly. These cheeses include Havarti, Feta, Swiss, Gouda, Gruyère, Provolone, Parmigiano-Reggiano and raw unpasteurized Cheddar.Apple cider vinegar: When yeast gobbles up the sugar in apples, fermentation occurs and ACV is born. Those tan strands floating in your bottle of health-boosting ACV are actually clumps of yeast and bacteria.Pickles: Not all pickles are created the same. Fermented pickles are ones made in a brine of water and salt, not vinegar. Some brands include Bubbies, Ba-Tampte and Kruegermann.Soy sauce: The salty-umami flavor of this popular Asian condiment develops from fermented soybeans.Beer: OK, so it’s not health food and you definitely don’t want to overdo it, but beer is fermented. Other fermented booze includes wine, mead and sake. Cheers!

Up next: What Are Probiotics—and How Do They Benefit Your Gut Health?

Sources

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