Think twice before cutting into that juicy steak for dinner or downing an energy drink to get a late-afternoon buzz. And if you’re a regular “consumer,” you may want to rethink your diet completely.
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Cleveland Clinic researchers found that when processed in the gut, carnitine (abundant in red meat and added to popular energy drinks) is metabolized to trimethylamine-N-oxide (TMAO), a compound linked to clogged arteries (atherosclerosis).
Watch to learn more about TMAO
Carnitine is not just in red meat; it is used in energy drinks and body building supplements.
More meat, more risk
The more you indulge, the greater your risk, according to the research. That’s because bacteria living in the human digestive tract metabolize carnitine, turning it into an organic compound called trimethylalamine (TMA), which is rapidly converted to TMAO by the liver. A previous study dating back to 2011 has linked TMAO to clogged arteries.
Meanwhile, a diet high in carnitine shifts our gut “biology” so meat eaters actually generate more TMAO and compound their risk of cardiovascular disease.
About the study
All this comes from a study at Cleveland Clinic led by Stanley Hazen, MD, PhD, Vice Chair of Translational Research for the Lerner Research Institute and Section Head of Preventive Cardiology & Rehabilitation.
The study compared carnitine and TMAO levels in omnivores, vegans and vegetarians. Carnitine levels were higher in omnivores. Those with meatless diets did not produce significant levels of TMAO. When Hazen’s team gave the meat eaters antibiotics to wipe out the gut bacteria, their levels of TMAO dropped, and no TMAO was made from ingested carnitine – therefore, they found that it is the gut bacteria that is required to produce the artery-clogging TMAO.
An expert’s advice
Dr. Hazen says you don’t have to stop eating meat all together. His suggestion: “Limit that steak to an occasional treat, and make it a smaller portion, too.”
Also important to note: carnitine is not just in red meat; it is used in energy drinks and body building supplements.