Is There any Possible Association Between Trimethylamine N-Oxide (TMAO) and Cancer? A Review Study

Background: During the transit of digested animal source foods, gut microbiota synthesize metabolites that can affect the body cells. One of these metabolites, i.e. Trimethylamine (TMA) that is an intermediary metabolite, ultimately leads to the production of Trimethylamine N-oxide (TMAO). Several studies have been conducted to show the association between TMAO and different diseases. This article aimed to search literature in order to review published findings about the possible association between TMAO and cancer. Materials and Methods: In this literature review, a comprehensive electronic search of different databases was done using "Trimethylamine N-oxide" and "cancer" as the main keywords. Result: Research suggests that TMAO can be related to the increased risk of cancer. The results showed a higher level of serum TMAO in cancer patients, most importantly colorectal cancer (CRC), than in healthy controls.  Nevertheless, inflammation, oxidative stress, and DNA damage could be the reasons for the link between TMAO and cancer. Limiting dietary intake of animal products can reduce levels of TMAO. Conclusion: It is concluded that a higher rate of TMAO production could potentially be associated with the development of different types of cancers, particularly CRC.