Saturated fat and cholesterol aren't the only reasons red meat can be harmful to your heart. Researchers from the Cleveland Clinic in Ohio recently discovered that a compound called carnitine, which is abundant in red meat, gets broken down into trimethylamine-N-oxide (TMAO) by a particular bacterium in the gut. TMAO can cause arteries to harden or clog, raising the risk of heart attack, stroke, and cardiovascular-related death.
According to lead researcher Dr. Stanley Hazen, the more meat you eat, the more of this TMAO-making bacterium you'll likely have in your gut. His team tested carnitine and TMAO levels in almost 2,600 meat eaters, vegetarians, and vegans. Both compounds were highest among meat eaters, since their gut bacteria were regularly given plenty of carnitine to feast on, helping them to multiply – and setting off a potentially vicious cycle. "Our research shows chronic dietary patterns influence the amount of TMAO production from carnitine," Hazen says.
Oddly enough, energy drinks – not something we usually say in the same sentence as steak – also contain lots of carnitine and can be equally, if not more, troublesome in this regard, says Hazen. "Many energy drinks have more carnitine per can than a porterhouse," he says.
Carnitine in itself isn't bad. In fact, it's available as a supplement and some studies show its health benefits. But how our body handles carnitine – especially in excess – is beginning to concern health experts like Hazen.
At the end of the day, this is just more reason to keep your steak splurges and Monster Energy consumption to a minimum.