Could Your Breath Reveal What Your Gut Microbiome Is Doing?

A simple breath test could one day provide a window into the activity of our gut microbiome.

A recent study published in Cell Metabolism shows that the gut microbiota contributes directly to the profile of volatile organic compounds (VOCs) found in exhaled breath.

The researchers first studied children and found that their breath volatilome was associated with both the composition and functional characteristics of their gut microbiome. They then used controlled gnotobiotic mouse models to demonstrate something particularly important: gut bacteria themselves can contribute to molecules that eventually appear in the breath.

As a proof of concept, breath profiles could also predict the abundance of Eubacterium siraeum, a bacterium associated with asthma in children.

The implications could be important.

Today, studying the gut microbiome generally requires stool collection, sequencing and complex analysis. Breath could potentially offer something very different: a rapid, non-invasive way to monitor microbial activity.

We are not yet at the point where a breath test can routinely diagnose the state of someone's microbiome. But this study opens an intriguing direction for microbiome medicine:

Could we eventually monitor the gut without directly sampling the gut?

This emerging field of microbiome diagnostics and functional biomarkers will be among the strategic topics discussed at Targeting Microbiota 2026 in Málaga, November 4–5.

Reference: Hernandez-Leyva AJ et al. The gut microbiota shapes the human and murine breath volatilome. Cell Metabolism. 2026.

For more information:

Read the full news here

Read the news on LinkedIn