Are probiotics the answer to a healthy microbiome?

Over-the-counter probiotics are not highly regulated, so you don't know really what you're getting, says gastroenterologist Chris Damman.

Probiotics have become the “in” thing, as a casual glance at the headlines as well as TikTok feeds shows.

But do they really work?

For UW Medicine gastroenterologist Dr. Chris Damman, the answer is “maybe.”

Damman has studied the microbiome and its effects on health for 20 years.  His focus has been on the microbiome's role as a protector against inflammatory bowel disease, metabolic disease and malnutrition.

“There are plenty of over-the-counter probiotics that you can get either in the refrigerated section or off the shelf at a pharmacy or supermarket,” said Damman. “The problem with a lot of those is they're not highly regulated. So, you don't know really what you're getting.”

At least one study has shown that certain probiotics may prevent the natural microbiome from repopulating your gut after a course of antibiotics.

His recommendation: Talk with your doctor first. Second, eat foods that your microbiome likes to snack on, like fiber. Fibers are carbohydrates that our body can't absorb. They make their way down into the last part of the small intestine and colon where they promote the growth of our own natural microbes.

Much of the work of promoting a healthy microbiome (Bifidobacterium and certain healthy Clostridium species) centers on putting the right foods and nutrients back into your diet.

“What food processing has taken out might be starving your gut microbiome,” said Damman, referring to the trillions of bacteria and fungi that live in one’s gut. “People focus on the nutrients their body needs when they eat, but they haven’t focused as much on the nutrients their microbiome needs.”

Symptoms of an unhappy gut include constipation and diarrhea, as well as gas, abdominal pain, or heartburn. Even in the absence of gastrointestinal symptoms, an unhappy gut can lead to symptoms in the rest of the body like dysregulated appetite, low energy, and even poor sleep, so it especially important to treat you gut microbiome well.

The full gamut of microbiome-promoting nutrients Damman refers to as the four phonetic F’s of food:  fibers, healthy fats, phenols, and fermented foods.  Fibers are in particularly high amounts in whole grains (such as oatmeal), nuts, seeds, and beans. Healthy fats include those in olives, avocados, and their oils that are high in omega-3 fatty acids. Phenols give the colors of the rainbow to fruits and vegetables. Think blueberries, red peppers and purple cabbage. Fermented foods include brined pickles, sauerkraut, kimchi and yogurt. 

“I call the fermented foods nature’s probiotic,” he said. “The bacteria come prepackaged with the foods they like to eat and the bioactive molecules they produce that are equally important for health.”

Damman tells patients who ask him about probiotics that unless they are looking to treat a certain condition, to go enjoy some sauerkraut or yogurt instead. Fermented foods have been shown to decrease inflammation in the body and increase the diversity of the microbiome in your gut.

“If you revamp your microbiome by focusing on the nutrients the microbes consume, they will produce metabolites like butyrate that stimulate the body to naturally produce factors like GLP-1, a blockbuster drug for diabetes and obesity, that helps reset the metabolism, blood glucose regulation, and appetite,” he said.

Other factors beyond diet that can help support a healthy microbiome include exercise, sound sleep and mindfulness. 

Getting a good night's sleep and reducing stress affects your gut and the rest of your body, Damman noted. Research shows that anxiety increases the stress hormones in your body which can compromise the gut barrier and lead to stimulation of the immune system and inflammation.

“The microbiome is almost like the gateway to the whole health of the body,” Damman said.

Written by Barbara Clements, 253-740-5043,

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Tags:food / nutritionprobioticsgut microbiome

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