Gut-Brain Axis: How Your Digestive System Shapes Your Mood and Health
When you feel nervous and get butterflies in your stomach, you’re not just imagining it—you’re experiencing the gut-brain axis, a two-way communication system between your digestive tract and your central nervous system. Also known as the enteric nervous system, it’s why stress can cause diarrhea, why anxiety makes you lose your appetite, and why fixing your gut can sometimes lift your mood. This isn’t just theory. Studies show that over 90% of the serotonin in your body—your main "feel-good" chemical—is made in your gut, not your brain. That means what’s happening down there directly affects how you think, feel, and react to stress.
The microbiome, the trillions of bacteria living in your intestines is the star player here. These tiny organisms don’t just help digest food—they send signals to your brain through nerves, hormones, and even your immune system. When your microbiome is out of balance—thanks to antibiotics, processed food, or chronic stress—it can trigger inflammation that shows up as brain fog, anxiety, or even depression. On the flip side, eating fiber-rich foods, fermented products, or taking probiotics can calm that inflammation and help your brain feel more stable. It’s not magic. It’s biology.
Your digestive system, a complex network from mouth to colon isn’t just a food chute. It’s a command center. When you have irritable bowel syndrome, Crohn’s, or even just occasional bloating, your brain gets constant low-level alerts. That’s why people with chronic gut issues often report higher stress levels. And when you’re stressed, your gut tightens up, slows digestion, and lets bad bacteria take over—creating a loop that’s hard to break. But breaking it is possible. Many of the articles below show real cases where people improved their gut health and saw changes in their anxiety, sleep, or migraines. You’ll find comparisons between medications that affect the gut-brain axis, like tibolone and clarithromycin, and how they interact with stress and immunity. You’ll also see how things like pollution, menopause, and diabetes tie into this system—not because they’re unrelated, but because they all influence inflammation, hormones, and microbial balance.
What you’ll find here isn’t just a list of articles. It’s a map of how your body really works. The gut-brain axis connects everything—from your allergy spray to your diabetes meds, from your pregnancy test stories to your bone loss after menopause. If you’ve ever wondered why your mood changes after eating, or why your stomach acts up before a big meeting, these posts give you the why—and the how to fix it.
- By Percival Harrington
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- 21 Oct 2025
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