Trimethylamine-N-Oxide: Friend, Foe, or Simply Caught in the Cross-Fire?

Trends Endocrinol Metab. 2017 Feb;28(2):121-130. doi: 10.1016/j.tem.2016.10.005. Epub 2016 Nov 5.


Trimethylamine-N-oxide (TMAO), a gut-derived metabolite, has recently emerged as a candidate risk factor for cardiovascular disease and other adverse health outcomes. However, the relation between TMAO and chronic disease can be confounded by several factors, including kidney function, the gut microbiome, and flavin-containing monooxygenase 3 (FMO3) genotype. Thus, whether TMAO is a causative agent in human disease development and progression, or simply a marker of an underlying pathology, remains inconclusive. Importantly, dietary sources of TMAO have beneficial health effects and provide nutrients that have critical roles in many biological functions. Pre-emptive dietary strategies to restrict TMAO-generating nutrients as a means to improve human health warrant careful consideration and may not be justified at this time.

Keywords: chronic diseases.; flavin-containing monooxygenase 3; gut microbiome; trimethylamine-N-oxide.

Publication types

  • Review
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Chronic Disease
  • Humans
  • Methylamines / chemistry*
  • Oxides / chemistry
  • Oxides / metabolism*
  • Oxygenases / metabolism


  • Methylamines
  • Oxides
  • Oxygenases
  • dimethylaniline monooxygenase (N-oxide forming)
  • trimethylamine

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