Biomarkers · Cardiometabolic

Trimethylamine N-oxide (TMAO)

Lower values go with lower risk of death. Not measured in our NHANES panel. The curve is drawn from the published study (source below).

TMAO and risk of death

Published curve higher than the NHANES fitNHANES fit higher

Risk of death relative to the curve's reference value, drawn from the published study (source below).

Published risk of death1.07×per each 10 umol/L increment of TMAO (dose-response, seven studies) (95% CI 1.04–1.11) · Meta-analysis of 17 clinical studies (n=26,167), mostly patient cohorts; dose-response based on seven studies

What studies found when this marker was changed

They describe what happened in those study groups, not a recommendation. See all catalogued interventions.

Measured changes in TMAO, study by study

2 effects with a numeric size, each from one study arm: the dot is the reported change, the line its 95% interval where one was given. Green points move the marker the way lower risk of death lies; amber the other way. Study results in the groups studied, not predictions for a person.

Each row is one study: what was changed, the effect it reported on this marker, and the source.
Type	Intervention	Reported effect	Evidence	Source
supplement	Probiotic supplementation in adults (8 RCTs, 270 participants)	No significant effect on plasma TMAO: -0.08 umol/L (95% CI -0.76 to 0.60)	meta-analysis	Sohouli MH, et al. Clinical nutrition ESPEN. 2022. Impact of probiotic…

Things that worsen it

Each row is one study: what was changed, the effect it reported on this marker, and the source.
Type	Condition or exposure	Reported effect	Evidence	Source
pharmacologic	SGLT-2 inhibitor (empagliflozin or dapagliflozin) vs placebo in type 2 diabetes, two randomised crossover trials	Plasma TMAO was 11.5% higher on an SGLT-2 inhibitor than on placebo (p = 0.006); 123 patients, duration not stated	RCT	Zimmer KB, et al. Endocrinol Diabetes Metab. 2026;9(6):e70318.

Sources

Risk curve: Schiattarella 2017 (PMID 29020409): all-cause RR 1.07 (1.04-1.11) per each 10 umol/L increment of TMAO (dose-response, seven studies). Scaled to published population values.
Schiattarella et al. Gut microbe-generated metabolite trimethylamine-N-oxide as cardiovascular risk biomarker: a systematic review and dose-response meta-analysis. European heart journal. 2017;38:2948-2956.

Map Trimethylamine N-oxide (TMAO) against another biomarker.

Map TMAO against another marker