Wisdom for Caring Well—Body, Mind, and Spirit

When most people think about digestion, they imagine their stomach breaking down food. But we know digestion is not a single process — it’s an elegant, interconnected system touching nearly every part of human health.

 

If your gut isn’t working well, your energy, mood, immune system, hormones, and even your brain function won’t work well either. That’s why the digestive system sits at the center of the Functional Medicine Matrix — the node called Assimilation. It’s responsible for digestion, absorption, the microbiome, and the integrity of your gut lining.

 

Let’s walk through how your gut works and why it’s considered your “second brain.”

 

 

Digestion Has Two Jobs: Break Down Food and Absorb It

 

For your body to use nutrients, two things must happen:

 

Breakdown
Proteins, fats, and carbohydrates enter your gut as large, complex molecules. Your digestive system breaks them down into small, absorbable pieces.

 

Absorption
Once food reaches the right area of the small intestine, it must cross the gut lining efficiently — but only the things your body wants to absorb.

 

When either step breaks down, symptoms arise: bloating, gas, nutrient deficiencies, inflammation, and low energy.

 

 

The Mind–Gut Connection: A Two-Way Street

 

Your mental and emotional state directly affects digestion — and your gut directly affects your mood.

  • Stress slows digestion or accelerates it → causing constipation, diarrhea, or loss of appetite.
  • Emotional tension tightens the gut wall → increasing sensitivity and dysbiosis.
  • The gut produces ~90% of your serotonin → impacting mood, motivation, and sleep.
  • Poor gut health sends inflammatory chemicals to the brain → contributing to depression.

 

No system in the body responds more quickly to stress than your digestive tract.

 

 

Why the Gut Lining Matters

 

The gut lining contains millions of cells joined together by “tight junctions.” These cells choose what gets absorbed into your bloodstream.

 

When the lining is damaged, the junctions loosen — a condition called increased intestinal permeability, or “leaky gut.”

 

Leaky gut:

  • Allows food particles and toxins into the bloodstream
  • Triggers the immune system
  • Creates inflammation throughout the body
  • Alters brain chemistry
  • Contributes to autoimmunity

 

This is why Functional Medicine places gut repair at the foundation of nearly every healing plan.

 

 

Your Microbiome: 100 Trillion Teammates

 

Your gut is home to a vast ecosystem of bacteria, fungi, and microbes — collectively known as the microbiome.

A healthy microbiome:

  • Supports digestion
  • Protects the gut lining
  • Balances the immune system
  • Reduces inflammation
  • Helps produce vitamins and neurotransmitters
  • Communicates directly with the brain

 

An unhealthy microbiome (dysbiosis) does the opposite — promoting inflammation, infection, mood changes, and chronic disease.

 

 

A Happy Gut Begins with the Basics

 

Functional Medicine always returns to the fundamentals:

  • Eat real, whole foods
  • Manage stress
  • Support digestion with proper chewing
  • Protect your gut environment
  • Rebuild the lining and microbiome when needed

 

When you optimize digestion, you optimize nearly every system in your body.

 

Stay tuned for Blog #2 in this series, where we explore the most overlooked pillars of gut health — chewing, acid levels, hydration, and mindful eating.