How Fermented Foods Can Help Support a Healthy Gut Microbiome

Cultures across the globe have been fermenting foods for centuries. Dutch sailors relied on the preserved nutrients in sauerkraut to combat scurvy. And let's not forget the colorful and illustrious history of wine…. And yet this ancient tradition has become something of a health food trend. Whole Foods has listed fermented foods on their Top 10 Foods Trends for the past five years.

Perhaps it is because food preparation and preservation technology have changed so much in recent decades. We had become so accustomed to heavily processed food that we didn't know what we were missing. Then approximately a decade ago, the research on the gut microbiome began. We finally understood that what we eat doesn't just affect our waistline, but an entire network of bodily functions and disorders that range from diabetes to neurodegenerative diseases. Perhaps that's when the switch flipped, and fermentation went from being an archaic food preservation method to one of the best ways to boost both shelf life and nutritional value.

The difference between fermentation and pickling

Just because technology changed doesn't mean we gave up on our pickles. But not all pickles are made equal.

Pickling is a preservation process in which food is cooked and then soaked in something sour (usually vinegar). Fermented foods sour naturally when the carbohydrates in the food react with naturally occurring bacteria; maybe there is some salt or brine involved. So, a pickle—the cucumber variety that appears on your hamburger—can either be pickled (most likely) or fermented. Only the fermented pickle has probiotics that aid in digestion, though.

To ensure that you're getting probiotic foods, look for the words “naturally fermented,” “contains live/active cultures,” and “raw” on the packaging.

Eating your way to a longer life

As with everything you eat, fermented foods affect your microbiome. But unlike prebiotics (which feed the microflora in your gut), fermented foods add to it.

Hosting anywhere between 4-6 different strains of bacteria in a single culture, yogurt is an excellent source of probiotics. It is one of those ubiquitous foods that can be consumed for breakfast or as a mid-afternoon snack, in a smoothie, or in a dressing. And as a popular, widely available food, it is also one of the most researched.

In one study, daily yogurt consumption regulated both gestational weight, blood pressure, and heavy metal toxicity in pregnant women. It is associated with reduced risk of type 2 diabetes and even reduced risk of overall mortality.

So there you go. Eating fermented foods can literally help you live longer.

What to put on your grocery list

Still at a loss on how to incorporate fermented foods into your diet? Look for these at your local grocery store.

Kombucha. This fizzy tea is seeing a surge in popularity. Kombucha is the product of a colony of bacteria and yeast—a “mother”—that feeds off added sugar and the tannins in the tea. Taking a swig of this drink will give you 10 billion CFU/gram.

Kefir. Another dairy product, but this is made using kefir grains (a combination of bacteria and yeast) to create a tangy drink. With fewer CFU than yogurt but more than kombucha, kefir weighs in at 70 billion CFU/gram.

Sauerkraut. This hot dog staple can be eaten as a side dish or a condiment. As with pickles, it's best to go with the raw type found in the refrigerated section at the grocery store. Raw sauerkraut can have upwards of a trillion CFU/gram.

Kimchi. This Korean version of sauerkraut is packs a punch with plenty of spices. There are hundreds of varieties, however, so you can experiment with what flavors and textures you like best. Like sauerkraut, kimchi contains more than a trillion CFU/gram.

Miso. This popular soup flavoring is a paste made from fermented soybeans. Miso is very salty so it may not be the best option is you have issues with sodium. And be careful when adding to hot broth; you don't want to kill the 100 billion CFU/gram.

Tempeh. Made from cooked and fermented soybeans, tempeh is a favorite of vegans for its nutty flavor and substantial texture. This better-than-tofu soy product weighs in at 10 billion CFU/gram.

Seaweed. Okay, so this isn't technically a fermented food, but seaweeds contain a carbohydrate called porphyrin that certain strains of Bacteroides have a difficult time living without. So, if microbial diversity is the name of the game (and it should be!) then seaweed is an important prebiotic.