Chances are, you’ve been sleeping on fermented foods for most of your life. Here in the US, they’re “not a natural part of our diet like in a lot of other populations,” Amy Burkhart, MD, RD, a physician and registered dietitian who specializes in gut health, tells SELF. Germany has sauerkraut, Korea has kimchi, China has stinky tofu, Japan has miso, but Americans—ever behind gastronomically—don’t have a signature fermented dish.
But interest in fermented food is growing steadily as people become more cognizant of its far-reaching benefits for the gut. And unlike some contemporary nutrition trends (looking at you, protein craze), it’s not all hype: Eating a diet rich in fermented foods really is a big win for your digestion, Alma Simmons, RDN, a registered dietitian at the Ohio State University Wexner Medical Center, tells SELF.
Below, we’ll break down how exactly fermented foods translate into a digestive boost; which fermented foods are best; whether fermented foods pose any health risks; and what you should keep in mind if you’d like to incorporate them into your diet more often. (Number one: “Don’t be wary of trying them!” Dr. Burkhart says.)
Why are fermented foods so good for gut health?
Fermentation involves the breakdown of carbohydrates like sugars and starches by beneficial microorganisms like bacteria, yeasts, and molds, especially lactic acid-producing bacteria. In nutrition-speak, these microorganisms are often termed “probiotics.” When you ingest these microbes in fermented foods, drinks, or probiotic supplements, they can positively affect your digestive system in a multitude of ways. Not only do they support your gut microbiome—the collection of microorganisms that live in your digestive tract—but they also strengthen the tissue that lines the gut (a.k.a. the “gut barrier”), improve your body’s ability to absorb nutrients, and reduce digestive symptoms like gas, bloating, and diarrhea.
In addition to their GI effects, these microbes can also benefit your health in other ways. They reduce inflammation, mediate your immune response, balance blood sugar, and lower harmful LDL cholesterol and triglyceride levels. Plus, “there is some evidence that they can improve mood and cognition,” Dr. Burkhart says. What’s more, she notes, many of these non-digestive perks may boost digestive health indirectly—a “circular effect.” Inflammation, for example, is widely believed to be a factor in autoimmune conditions, including digestive disorders like IBD and celiac disease, so by that token decreasing it could further reduce symptoms.