5 Signs Your Gut Microbiome Is Off (and How to Rebuild It)

By Baldomero Garza, Co-Founder, MSW Nutrition

If you deal with bloating, brain fog, low energy, or cravings you can't explain, the root cause may be lower than you think. Your gut microbiome — the trillions of microbes living in your digestive tract — influences far more than digestion. It helps regulate your mood, immune system, hormones, energy, and even your brain. When that microbial balance slips, the warning signs rarely look like "gut problems," which is exactly why they get missed.

Below are five research-backed signs your gut microbiome is out of balance, plus a practical plan to start rebuilding it.

What your gut microbiome actually does

Your gut is home to trillions of bacteria (and some fungi and viruses), most of which work for you. They break down what you eat, protect the intestinal lining, train your immune system, and manufacture the neurotransmitters that shape how you feel. Researchers describe a two-way gut–brain axis: a constant exchange of signals between the gut and the brain that influences cognition, mood, and long-term brain health.²

When the balance of those microbes shifts — what scientists call dysbiosis — that communication breaks down. And because the same microbes touch digestion, immunity, blood sugar, and brain chemistry, the symptoms can appear almost anywhere.¹ If you want the full reset framework, our ultimate guide to restoring gut health walks through it step by step.

5 signs your gut microbiome is off

1. You've taken antibiotics

Antibiotics are essential, life-saving medicine — but they don't discriminate. Each course can clear out beneficial bacteria along with the harmful ones, and the composition of the microbiome can stay altered afterward.³ Without intentional rebuilding with fiber, fermented foods, and targeted support, that loss can linger for far longer than the infection it treated.

2. You have brain fog

Because so many neurotransmitters originate in the gut, a disrupted microbiome can leave you mentally cloudy, unfocused, or flat — long before anything feels "wrong" with digestion. Gut microbes help produce serotonin, dopamine, and GABA, the chemical messengers behind focus, mood, and calm.² When production drops, your brain feels it first.

3. You have an autoimmune or inflammatory condition

A growing body of research links microbiome imbalance and a compromised gut barrier to autoimmune and inflammatory conditions.¹ The gut lining is a frontline filter; when it becomes permeable, the immune system is exposed to things it shouldn't be, and chronic inflammation can follow.

4. You crave sugar

This one surprises people. Certain gut bacteria feed on sugar and effectively "ask" for more of it. A high-sugar diet shifts the microbial balance and is associated with lower natural production of GLP-1, the hormone that helps regulate appetite.⁵ In other words, that relentless "food noise" may be less about willpower and more about who's living in your gut.

5. You don't go every day

Irregular digestion is the most direct signal of all. Daily, comfortable elimination is one of the simplest markers of a gut that's working with you. If you're not regular, your microbiome is usually trying to tell you something — our guide on 5 steps to fix your gut health is a good place to start.

How to rebuild your gut microbiome

The good news: the microbiome is one of the most responsive systems you have. A few consistent inputs go a long way.

1. Crowd out the sugar. Lean into whole, one-ingredient foods and a Mediterranean-style pattern. Starving the sugar-loving microbes is step one.
2. Feed the good bacteria. Add fiber-rich vegetables and fermented foods to repopulate beneficial strains.
3. Use omega-3s as a prebiotic. High-quality fish oil helps nourish the microbiome and supports the GLP-1 pathway.⁶
4. Support the gut-liver connection. Your liver and gut work as a team; supporting healthy detox and bile flow keeps the whole system moving.
5. Target blood sugar and the gut lining. Nutrients like berberine and L-glutamine support metabolic balance and the intestinal barrier at the same time.⁷⁸ If you're curious about glutamine specifically, we cover it in should you supplement with glutamine?

Rebuild your gut in 60 days

The Good Poops Protocol pairs three MSW Nutrition formulas into one 60-day system: Gut (L-glutamine) for the intestinal lining, Liver Boost for detox and bile flow, and Berberine Plus (dihydroberberine) for blood-sugar metabolism and natural GLP-1 support — working together to address the root, not just the symptoms.

Try the Good Poops Protocol — $279 →

Want to start with just the gut lining? Gut delivers L-glutamine, the amino acid your intestinal cells use as fuel to stay strong and sealed — a simple first step toward fewer cravings and better digestion.

👉 Get Gut by MSW Nutrition →

References

1. Microbiota dysregulation and autoimmune disease (review). PMC11099291.
2. The gut microbiome, neurotransmitters, and cognition. PMC8234057.
3. Antibiotics, the microbiota, and the gut–brain axis. ScienceDirect, 2024.
4. Gut microbiota, sugar fermentation, and metabolic-associated fatty liver. PMC11927047.
5. Bacteroides vulgatus, vitamin B5, GLP-1, and sugar cravings.
6. Gut microbiota metabolites and GLP-1 secretion. PMC10790698.
7. Berberine induces GLP-1 secretion. ScienceDirect.
8. Glutamine, postprandial glycemia, and GLP-1. PMC7212026.

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