Constipation and Loose Stools: Why Digestion Swings Between Extremes

If you’ve ever thought:

  • “Some days I’m constipated, other days it’s loose.”

  • “Why does my digestion feel unpredictable?”

  • “Is it normal to alternate between constipation and diarrhea?”

From both a Traditional Chinese Medicine (TCM) and Western perspective, swinging between constipation and loose stools usually isn’t random. It’s a pattern, and patterns tell us far more than isolated symptoms.

Rather than asking, “What’s wrong with me today?”
Practitioners tend to ask, “What keeps repeating?”

Alternating Stool Patterns Aren’t Just About Food

It’s tempting to blame digestion entirely on what you ate yesterday. Sometimes that’s true. But when bowel habits swing back and forth over weeks or months, there’s usually something deeper happening.

In clinic, alternating constipation and loose stools often reflects instability in:

  • Digestive function

  • Fluid metabolism

  • Nervous system regulation

  • Stress processing

Your gut doesn’t operate in isolation. It responds to emotional load, sleep, hydration, hormonal shifts, and how safe your nervous system feels.

TCM and Western physiology both observe these same digestive patterns, just through different lenses.

A TCM Perspective: When Digestion Loses Its Rhythm

In Traditional Chinese Medicine, digestion is governed primarily by the Spleen and Stomach. Their job is to transform food into usable energy and move fluids appropriately through the body.

When this system is steady, stool tends to be regular and formed.

When it’s disrupted, patterns emerge.

Here are three common TCM frameworks that help explain alternating stool consistency:

1. Spleen Qi Deficiency

This reflects weakened digestive transformation.

You might notice:

  • Loose or unformed stool

  • Fatigue, especially after meals

  • Bloating

  • Brain fog

  • Low appetite

When the Spleen isn’t extracting nourishment efficiently, stools may become loose. Over time, this weakness can also contribute to sluggish movement in the intestines - leading to constipation on other days.

2. Liver Qi Stagnation Overacting on the Spleen

This is one of the most common patterns I see, especially in people under chronic stress.

In TCM, the Liver is responsible for smooth flow throughout the body. When stress, emotional tension, or feeling overwhelmed causes Liver Qi to stagnate, digestion often takes the hit.

This can show up as:

  • Alternating constipation and loose stools

  • Digestive symptoms that worsen with stress

  • Abdominal tightness or cramping

  • Irritability or emotional reactivity

In simple terms, stress disrupts digestive rhythm. One day, things feel stuck. Next, everything moves too quickly.

3. Dampness vs Dryness Patterns

TCM also looks at fluid balance.

Some people lean toward dampness:

  • Loose or sticky stool

  • Heaviness

  • Bloating

  • Fatigue

Others lean toward dryness:

  • Hard stool

  • Pebble-like bowel movements

  • Dry mouth or skin

When the body swings between these states, digestion feels unpredictable.

This often reflects inconsistent fluid metabolism combined with nervous system stress.

A Western Herbal Perspective: The Gut–Brain Connection

Western physiology tells a similar story.

The digestive tract is deeply influenced by the nervous system. When you’re stressed, rushed, or emotionally taxed, your body shifts into sympathetic mode (fight or flight). Blood flow moves away from digestion. Motility changes and absorption is affected.

This can lead to:

  • Constipation during high stress

  • Loose stools when the system finally releases

  • Alternating patterns depending on your emotional state

Other contributors include:

Fiber Imbalance

Too little fibre can slow motility. Too much (especially without enough hydration) can worsen bloating or constipation.

Magnesium

Magnesium supports muscle relaxation in the gut. Low levels may contribute to constipation, while higher doses can loosen stools.

Bitters and Mucilage Herbs

Bitters stimulate digestive secretions and help “wake up” sluggish digestion, while mucilaginous herbs soothe, protect, and gently hydrate the intestinal lining.

Mucilaginous herbs like Marshmallow root and Slippery Elm are often used to calm irritation and support tissue integrity, especially when digestion feels inflamed or dry.

Bitter herbs such as Gentian, Wormwood, and Angelica archangelica work differently; they encourage bile flow and digestive activity, which can be helpful when digestion feels heavy, slow, or stagnant.

These are tools practitioners use thoughtfully and selectively, based on the person and their overall pattern, not blanket recommendations.
Different patterns require different approaches; what soothes one person’s digestion may aggravate another’s.

Why Practitioners Look at Patterns Over Time

Here’s the key point:

Alternating constipation and loose stools usually means your system is struggling to find equilibrium.

Rather than chasing each symptom separately, practitioners look for:

  • What repeats

  • What triggers flare-ups

  • How stress affects digestion

  • Whether fatigue, sleep, or emotional load are involved

The body rarely sends mixed signals without reason. Digestion often speaks early, long before bigger symptoms appear. Your health is reflected throughout your body; it’s constantly communicating, and the work is learning how to listen and pay attention. And yes.. You should always look at your stool to see what’s going on!

In closing

If your digestion feels inconsistent or unpredictable, it doesn’t mean you’re broken. It usually means your system is asking for steadier support.

In both TCM and Western herbal medicine, the goal isn’t to suppress symptoms - it’s to restore rhythm, balance fluids, and support digestion in a way that fits your unique pattern.

If your digestion feels inconsistent or unpredictable, working with someone who looks at the whole pattern, not just individual symptoms, can be helpful.

I explore digestive patterns regularly in clinic here in Victoria, BC using acupuncture, herbal medicine, and lifestyle support.

Avery Knechtel