Paging Dr. Frischer: TMAO

Now here is something useful: a new lab test to predict your risk of a heart attack. Thanks to the work at the Cleveland Heart Clinic, TMAO has been discovered. What is it? How does it help?

TMAO (trimethylamine N-oxide) is a compound produced by the liver after intestinal bacteria digest certain nutrients. It affects how cholesterol accumulates in tissues, particularly the artery wall. High levels of TMAO indicate an increased risk for developing atherosclerosis, which can lead to heart attack, stroke, and death.  

What are these gut bacteria, and why are they important? On the internal lining of our digestive tract are trillions of microorganisms. The bulk of these microorganisms are critically important bacteria. Each of us has a unique composition of these gut bacteria. Among their many jobs are to produce essential vitamins and to help us digest food. They also form a barrier between the contents of the intestines and the blood stream, continuously combating invasive and disease-causing bacteria.  

Our diet influences our gut microbe composition. Red meat, eggs, and high-fat dairy are high in phosphatidylcholine, choline, or L-carnitine, which provide the material needed for gut bacteria to start producing TMAO. In contrast, vegans and vegetarians produce very little TMAO. 

The reason to check TMAO levels is to determine whether your diet is working for you, and whether more aggressive preventive efforts may be needed. To lower your TMAO level and encourage a healthier makeup of gut bacteria:

■      Consume more green leafy vegetables and fiber.

■     Avoid foods rich in TMAO precursors such as whole milk, eggs, fatty yogurt, cream cheese, ice cream, butter, and red meat like beef, pork, ham, lamb and veal.

■      Consider taking probiotics regularly.

■     Avoid dietary supplements or energy drinks that contain phosphatidylcholine/choline or L-carnitine.

Be on the alert for more information regarding TMAO blood tests. At present, this lab test can be obtained only from the Cleveland Heart Clinic and in a few practices across the United States. It is not yet available at our local standard labs. 

Dr. Alan Frischer is former chief of staff and former chief of medicine at Downey Regional Medical Center. Write to him in care of this newspaper at 8301 E. Florence Ave., Suite 100, Downey, CA 90240.