Age is a well-known risk factor for cardiovascular disease. Now, a new study has identified the link between gut metabolites and age-related heart disease. Whilst we cannot change our age, levels of this metabolite can be managed through our diet.   

By Sujita Pandey It is evident through various researches that aging causes changes in the heart vessels and blood vessels1. Aging, therefore, poses the largest risk factor for cardiovascular disease as a result of oxidative stress to our arteries. The reason behind it is unknown, however, a recent study from the University of Colorado Boulder has identified a gut metabolite as a potential driver. The researcher for University has succeeded to show a visible confirmation that a metabolite, namely, trimethylamine-N-Oxide (TMAO) produced by gut microbiome contributes to age-related declines in cardiovascular health2

TMAO Spells Trouble

TMAO is a metabolic byproduct of digestion, that has been linked with heart disease in numerous studies. However, the exact cause of how it damages the cardiovascular system were not clear until now3. In the study, the scientists argue that TMAO can not only impair artery function, but also damage the cardiovascular system in a way that naturally occurs with age. 

There is a strong negative correlation between high blood levels of TMAO and cardiovascular health, therefore, consumption of high TMAO foods such as red meat, eggs, or other animal proteins should be limited.

There is a strong negative correlation between high blood levels of TMAO and cardiovascular health, therefore, consumption of high TMAO foods such as red meat, eggs, or other animal proteins should be limited.

Accelerated Aging

These new findings, published in journal Hypertension, are the first to illustrate how the cardiovascular system is damaged due to high TMAO. Conducted as a large cohort among healthy adults, the results suggested that TMAO blood levels increased in relation to age, regardless of heart or vascular health. What's more, there was a direct correlation between higher TMAO levels and worsening artery function among older adults.

There was a direct correlation between higher TMAO levels and worsening artery function among older adults.

Furthermore, an additional study conducted in mice showed that TMAO rapidly degraded vascular health among the young animals, too. After ingesting TMAO for several months, the vascular function of young mice was similar to old mice. 

Protective Plant Proteins 

On the the positive side, the levels of TMAO can be controllable through dietary modifications or drugs. The researchers notes that dietary interventions could be best for maintaining heart health in older age4. Notably, lowering consumption of animal products, such as red meat and dairy, can reduce levels of TMAO. Eggs can also be problematic. Eggs are rich in choline, which gets metabolized by gut bacteria into TMAO, thus contributing to the development of cancer and heart disease.5 For instance, a 2017 meta-analysis demonstrated that higher circulating levels of TMAO were associated with a 23% higher risk of cardiovascular events, a 55% increase in mortality.6

Higher circulating levels of TMAO were associated with a 23% higher risk of cardiovascular events, and a 55% increase in mortality.

Instead, opting for plant proteins, such as beans, tofu, tempeh, nuts and seeds, can have tremendously protective benefits. Sometimes, what we omit that more important than what we include. In this case, TMAO is produced from eating animal products, so reducing your intake holds a lot of power. 

References:

  1. Rodgers, J., Jones, J., Bolleddu, S., Vanthenapalli, S., Rodgers, L., Shah, K., Karia, K. and Panguluri, S., 2019. Cardiovascular Risks Associated with Gender and Aging. Journal of Cardiovascular Development and Disease, 6(2), p.19.
  2. Brunt, V., Gioscia-Ryan, R., Casso, A., VanDongen, N., Ziemba, B., Sapinsley, Z., Richey, J., Zigler, M., Neilson, A., Davy, K. and Seals, D., 2020. Trimethylamine-N-Oxide Promotes Age-Related Vascular Oxidative Stress and Endothelial Dysfunction in Mice and Healthy Humans. Hypertension, 76(1), pp.101-112.
  3. Papandreou, C., Moré, M. and Bellamine, A., 2020. Trimethylamine N-Oxide in Relation to Cardiometabolic Health—Cause or Effect?. Nutrients, 12(5), p.1330.
  4. Haridy, R., 2020. Age-related heart disease linked to gut bacteria metabolite. New Atlas, [online] Available at: <https://newatlas.com/health-wellbeing/age-cardiovascular-heart-disease-gut-bacteria-metabolite-tmao/> [Accessed 5 July 2020].
  5. Tang WH, Wang Z, Levison BS et al. Intestinal microbial metabolism of phosphatidylcholine and cardiovascular risk. N Engl J Med. 2013;368:1575–84.
  6. Schiattarella GG, Sannino A, Toscano E et al. Gut microbe–generated metabolite trimethylamine-N-oxide as cardiovascular risk biomarker: a systematic review and dose-response meta-analysis. Eur Heart J. 2017;38(39):2948–56.