IMO: The Slow-Gut Pattern Behind Constipation & Bloating

If constipation is your baseline… and bloating is your constant companion… you might be dealing with a pattern that’s often mislabeled, misunderstood, or simply missed: Intestinal Methanogen Overgrowth (IMO).

This isn’t a scary label. It’s a map. And when we name the pattern accurately, we stop chasing random protocols and start making decisions that actually match your physiology.

What IMO actually is

IMO is an overgrowth of methane-producing microbes called methanogens (they’re archaea, not bacteria). Their favorite fuel is hydrogen gas- so when fermentation happens in your gut, methanogens can “feed” on that byproduct and produce methane.

And methane has a very specific effect in the body:

It slows intestinal movement.

So instead of things moving forward smoothly, the gut gets sluggish. That’s why IMO so often shows up as the “stuck” pattern.

The IMO symptom vibe

IMO can overlap with other gut issues, but it has a signature feel:

  • constipation or incomplete emptying

  • bloating that builds as the day goes on

  • heaviness, pressure, or distension after meals

  • gas that doesn’t “move through” easily

  • feeling better when you finally have a solid bowel movement

And here’s the important part: when motility slows, the entire ecosystem shifts- more fermentation, more byproducts, more reactivity, more inflammation.

Why “just eat more fiber” doesn’t always work

A lot of people with IMO have tried the usual advice: more fiber, more probiotics, more fermented foods.

But when the gut is moving slowly, piling on fermentable material can backfire. It’s not that fiber is bad. It’s that timing and type matter, and your gut needs flow before it can handle more load.

The functional medicine approach

In my world, we’re not just trying to “kill something.” We’re rebuilding the conditions that make your gut feel safe, supported, and rhythmic again.

That usually means focusing on:

1) Motility first
Not harsh laxatives. Not panic. A steady plan that supports the gut’s natural housekeeping and forward motion.

2) Digestion support
Stomach acid, enzymes, bile flow (and bile balance), meal timing—these determine how much fermentation happens downstream.

3) Nervous system regulation
A stressed body doesn’t digest well. And a gut that feels stuck can keep the nervous system on high alert. We work both directions: physiology and safety.

4) Microbiome strategy- specific, not trendy
Probiotics and ferments can be amazing… at the right time. In IMO patterns, we often have to be more intentional about when and how we introduce them.

The “freedom phase” (yes, it’s possible)

The goal isn’t to live on a restricted diet forever. The goal is to restore enough rhythm that your gut can tolerate variety again- without the bloat spiral.

When the gut starts moving, people usually notice:

  • lighter belly

  • better appetite signals

  • less fear around food

  • steadier energy

  • and a nervous system that stops bracing after meals

That’s the shift. That’s where confidence comes back.

If you’re wondering if this is you…

If constipation is persistent, bloating feels predictable, and your body responds better to rhythm than restriction, IMO might be a pattern worth exploring.

If you want help making sense of your symptoms and building a plan that’s actually aligned with your body, you can book a SIBO Strategy Session with me. We’ll look at your history, your patterns, and the most supportive next steps, without protocol chaos.

Schedule your call when you’re ready. HERE

Your gut isn’t random. It’s responsive.
And we can work with that.

Jen Yundt Coles