Is Your Gut Microbiome Out of Whack? Here’s What it Is, and Why it Matters

image of folded paper in the shape of intestines

Making friends with “good” bacteria is key.

At this very moment, there are trillions of bacteria, viruses, and fungi hanging out inside of your intestinal tract. But there’s no reason to be concerned: This community living within us is referred to as the gut microbiome, and it’s crucial to maintaining our overall health. It plays a major role in digestion and immunity, has been implicated in everything from rheumatoid arthritis to heart health, and may even predict how well you age

But how do you keep your gut microbiome flourishing? What happens when it’s disrupted? And can probiotics really help? We turned to nutritionist and cookbook author Maya Feller for the lowdown on this complex system. 

What exactly is the gut microbiome?

Of the trillions of microbes that colonize your gut, some of them are beneficial. These “good” bacteria help digest and absorb the vitamins and minerals we need. They also produce antibiotics that kill “bad” bacteria, which if left unchecked, can cause disease. 

In recent years, researchers have zeroed in on the importance of cultivating the right mix of gut bacteria. Metabolic disorders like Type 2 diabetes, inflammation, and digestive conditions like irritable bowel syndrome (IBS) and Crohn’s disease have all been associated with less microbial diversity.

There’s also a growing body of evidence that the gut microbiome may play a role in the development of neurological conditions like Alzheimer’s disease and mood disorders, like depression and anxiety.

The list really goes on and on, Feller says. 

How can you promote a healthy gut?

Thankfully, we have some control over the composition of our microbiomes. Eating “whole, minimally processed foods” is one of the best things to support a healthy gut, Feller says. It’s also extremely important to consume enough fiber, through vegetables, fruits, beans, and other sources. 

“The gut loves fiber,” she says. “It acts as wonderful fuel and nourishment for the good gut bugs in there.”

These foods will promote microbial diversity, while diets high in sugar and alcohol will “decrease that good bug activity,” Feller says. There’s also some compelling research that fermented foods like yogurt, sauerkraut, kimchi, and kombucha also help create a wider array of gut bacteria. 

What’s the word on probiotics?

There are a ton of probiotic supplements available now that claim to boost the number of “good” bacteria in your gut, target your skin microbiome, or are formulated for vaginal health. But Feller says there are a few key things to keep in mind before giving them a try. 

First, consult a medical professional who can help you find a trusted supplement and determine if you really need one. If you’re suffering from small intestinal bacterial overgrowth (SIBO), for instance, a probiotic may actually lead to more gas and bloating, Feller says. If you do decide to take a supplement, start small. Most supplements contain between 1 to 10 billion colony-forming units (CFU), but some have up to 50 billion. You want to find something on the lower end of this spectrum. 

“The general thinking is to start with the lower amount of CFUs. Remember, you’re building up good bacteria, and if you go too hard, too fast, it’s kind of like smashing the system,” Feller says. “It can cause gas and bloating.”

Now, when it comes to probiotic yogurts, which seem to have proliferated in recent years, the key is to check the label for “live active cultures” and to “listen to your body,” Feller says. 

“If you’re over-consuming it, your body will tell you,” she says.