The Best Fermented Foods for Better Gut Health, According to a Gastroenterologist

When thinking about the best foods for gut health, one of the top things that may come to mind may be fermented foods. Foods that go through a fermentation process contain probiotics, which are essential for your gut microbiome and aid in health digestion. But what are the best fermented foods to help improve your gut health—and is there a “worst” option? We asked an expert to weigh in.

“From my perspective, there’s always a hierarchy in food,” gastroenterologist Will Bulsiewicz, M.D. says in a conversation with EatingWell. “There’s the foods that I would put at the top and the ones that would put at the bottom.”

There are two clear fermented food winners, plus the one that’s a least favorite of the doctor’s. Read on to find out what probiotic-packed foods to focus on and what to keep in mind on your next grocery trip.

The Best Fermented Food for Gut Health

What’s at the top of Dr. B’s list, you ask? It’s a tie between two plant-based options.

“When it comes to fermented food, I would put the fermented plants at the top,” he says. “So examples would be kimchi and sauerkraut.”

Kimchi and sauerkraut are not only delicious, but they’re also incredible for your gut bacteria. Bulsiewicz explains why: “These foods contain probiotics, but they also contain fiber and the prebiotics,” he explains. “Fermentation is about transformation, and transformation is not just adding bacteria to this process. It also includes the creation of acid. This is why sauerkraut is bitter, not just salty cabbage. The fiber is transformed and becomes brand new forms of fiber [that support your gut].”

With the ultimate combination of probiotics, prebiotics and fiber, fermented plants like sauerkraut and kimchi are clear winners. Pick them up pre-made on this week’s grocery run, or make them at home by following recipes like our Simple Sauerkraut and Homemade Kimchi.

The Worst Fermented Food for Gut Health

As Bulsiewicz explained earlier, for any category of food, he considers there to be a hierarchy. This means that there’s a fermented food at the bottom of the list—here’s his take on that.

“I don’t consider this unhealthy, but I do consider it a food that I consume in moderation—that would be kombucha,” he admits. “The base of kombucha is basically sweet tea, and that sweet tea does get transformed—the sugar, much of it gets consumed by the bacteria as a part of fermentation—but there’s still quite a bit of sugar left over.”

Kombucha, the popularized fermented tea drink, can help keep you hydrated, energized and it boasts the gut-healthy benefits of any fermented food. But as Bulsiewicz explains, kombucha can be high in sugar and added sugar, especially if you’re drinking a pre-packaged product. Try making your own kombucha at home with our Homemade Kombucha recipe to help control the sugar content.

The Bottom Line

All fermented foods are going to have gut-healthy properties, but some are better than others. While kombucha, by and large popular store-bought bottles, may not be the best choice for an everyday sip, it’s still a gut-supporting option that has healthier alternatives. And sauerkraut and kimchi are nutritious and tasty, so adding them to your next meal may be a good idea.