To learn more about subtle gut inflammation symptoms to keep an eye on, we reached out to Kenneth Brown, MD, a board-certified gastroenterologist based in Plano, Texas.

6 sneaky gut inflammation symptoms to see a physician about

1. Digestive issues

Again, perhaps the most obvious sign that your gut could use a lifeline is digestive upset, which often comes in the form of gas and bloating. “Bloating is caused by gas becoming trapped in the upper GI tract—most commonly [when] bacteria is breaking down food,” says Dr. Brown.

However, bacteria shouldn’t be present in this area of the digestive system. If it is, you may be dealing with gut inflammation in the form of small intestinal bacterial overgrowth (SIBO). Unlike the colon (where a healthy balance of bacteria should reside), the upper GI tract should be nearly sterile, he continues. “When the normal environment of the GI tract is altered with increased bacteria, it can disrupt your digestive health—causing bloating and other digestive issues such as abdominal discomfort, constipation, and diarrhea.” In more severe cases, inflammatory bowel disease (IBD) may be present if you experience these digestive symptoms as well as bloody stools.

2. Skin flare-ups

When your gut is inflamed, you may notice that your skin flares up as well. “The gut microbiome modulates the immune system’s response to inflammation, influencing the development and progression of skin conditions,” Dr. Brown explains.

For instance, dysbiosis (i.e., an imbalanced gut microbiome) could trigger or exacerbate acne, psoriasis, eczema, and rosacea. These specific dermatological conditions aside, your skin may become dryer or flakier than usual. That’s because your gut microbiome “affects the skin barrier’s integrity—which is essential for healthy skin—by producing compounds with anti-inflammatory properties that improve hydration,” he adds.

“The gut microbiome modulates the immune system’s response to inflammation, influencing the development and progression of skin conditions.”
—Kenneth Brown, MD, a board-certified gastroenterologist

In short, gut inflammation gets in the way of maintaining healthy, happy, and hydrated skin.

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3. Sugar cravings

Got a sweet tooth? Be aware that it doesn’t only have the potential to stoke gut inflammation but also trigger more cravings… and thus even more inflammation. “When you eat a diet rich in processed foods and sugar, your microbiome changes to favor the bacteria that like sugar,” Dr. Brown warns. “These bacteria release chemicals that signal your brain’s need for more sugar.”

While the whole shabang perpetuates a tough cycle to break free of, the GI doc advises giving your microbiome more of what it needs—like fiber and polyphenols—versus what your all-too-loud cravings are convincing you to want. These nutrients will basically silence the sugar-craving bacteria, notes Dr. Brown, allowing you to get your diet and your microbiome back on track. Fortunately, you can get this power duo in a variety of healthy, whole foods—including fruit, which is totally fair game as a swap to satisfy your palate.

4. Undesired weight loss

According to Dr. Brown, unintentional weight loss—namely on account of digestive dysfunction—can be serious. “Anything that causes inflammation like celiac disease, Crohn’s disease, or small intestinal bacterial overgrowth (SIBO) can cause weight loss,” he shares. So, too, can malabsorption, which he says can be caused by pancreatic insufficiency or SIBO. If you’re losing weight without trying and without changing much in your routine, he warns that this is a red flag and you should consult your physician ASAP.

5. Mood imbalances and brain fog

Moody, irritable, foggy? While these signs could point to a few things—perhaps the most infamous being PMS—they could also signal inflammation and imbalances in the gut given the intricacy of the gut-brain axis. “Signals sent along this axis allow your gut bacteria to communicate with your brain and vice versa, which can influence mood and behavior,” says Dr. Brown.

And let’s not forget that key neurotransmitters for mood and mental health—including serotonin, dopamine, and GABA—are produced in the gut. For instance, the gut creates about 95 percent of the body’s serotonin, but levels can get depleted when it’s in poor shape. As far as mind and mood are concerned, low serotonin levels are linked to everything from depression and anxiety to hostility and difficulty concentrating.

6. Fatigue and insomnia

These signs of gut inflammation can also manifest in large part due to serotonin’s involvement in regulating circadian rhythms. “Serotonin is the building block of melatonin, which is associated with keeping us in our proper sleep cycles. Research is proving that our guts are a major source of melatonin production,” Dr. Brown explains.

“If your microbiome isn’t in good shape, it can throw off your circadian rhythm and cause insomnia.”

As it turns out, the more melatonin, the merrier—not only for your shuteye but your gut microbiome, too. Per a 2023 review in the French scientific journal Biochimie, the hormone has the ability to alter the composition of intestinal bacteria to favor types with anti-inflammatory properties. (Pretty cool, right?) With that said, it’s worth doing what you can to boost levels of melatonin in the body—including but not limited to eating foods with melatonin and dimming the lights as you kick off your pre-ZZZ routine.

While gut health is only one piece of a larger puzzle that will impact your serotonin and melatonin levels, it still wields a big influence. “If your microbiome isn’t in good shape, it can throw off your circadian rhythm and cause insomnia,” he continues. (Not to mention that more stress and mood imbalances could also disrupt your energy levels and sleep patterns.)

To bounce back from gut inflammation, stick to standards like enriching your diet with fiber, polyphenols, prebiotics, and probiotics; exercising regularly; and finding your sweet spots for self-care and stress management. Better yet, set your day up for success by prioritizing these gut-healthy habits each and every morning.

—reviewed by Jennifer Gilbert, MD, MPH