Four Pillars of the gut · a clinical frame

Your chronic symptoms may not be failing to heal — you may be feeding them, daily.

Bloating, bad breath, brain fog, cravings, skin problems — scattered symptoms that often share one upstream source: bacterial overgrowth in the gut. And what fed those bacteria was frequently the food you were taught was "healthy." A clinical frame built on eight years of directly measuring patients' breath gases in Seoul.

Start here

Most readers arrive with one of these two.

The two most common entry points — and the best places to begin.

The overgrowth itself

SIBO — complete guide

What small intestinal bacterial overgrowth is, why it happens, how it's tested, and the counterintuitive part: why fiber, fermented foods, and probiotics can make it worse.

The most common symptom

Bloating & Gas

Why bloating gets worse the more fiber and probiotics you take, and how the smell of the gas tells you whether VSC-producing bacteria are overgrowing.

Reasoning notes

Take one symptom, and follow it upstream.

Instead of handing out a label, these anonymized composite notes show the line of reasoning that ties scattered symptoms back to a single root.

Who writes this

Eight years of measuring the gas, not guessing at it.

Neo-Skepticism is the clinical frame of June-sang Yang, MD, a physician in Gangnam, Seoul who has spent eight years directly measuring patients' breath gases — including hydrogen sulfide and methyl mercaptan, the gases standard panels miss. He is also the Korean translator of low-carb / high-fat books including The Big Fat Surprise (Nina Teicholz).

About June-sang Yang, MD →

Follow the full essay series.

The English-language writing on SIBO, VSCs, GLP-1, and the gut origins of chronic symptoms lives on Substack.

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