What does the Breath Methane test measure?

Why is Breath Methane measured?

Methane is the most robustly supported component of the panel. Elevated methane correlates with constipation-predominant symptoms and with a slower transit phenotype, and a level at or above 10 ppm at any timepoint is the recognised positive criterion. Because the responsible organisms are archaea rather than bacteria and the overgrowth is not limited to the small intestine, the entity has been formally reframed as intestinal methanogen overgrowth rather than as a subtype of SIBO, and this distinction carries treatment implications since methanogens respond differently to antimicrobial therapy.

Reference ranges

Standard reference

A level of ≥10 ppm at any point is consistent with methane positivity / intestinal methanogen overgrowth (IMO) # REVIEWER FLAG: Threshold based on the 2017 North American Consensus — reviewer to confirm against Genova's stated criteria.

Functional medicine optimal

Methane consistently below the positivity threshold is the expected normal pattern # REVIEWER FLAG: 'Optimal' framing not standardised.

Units

ppm

Reference ranges vary by laboratory and assay platform. Interpret in context of the issuing laboratory's stated range.