The Truth about L-Carnitine Side Effects

Filed Under: Heart Health, Nutritional Support

The Truth about L-Carnitine Side Effects

As you may have read or heard in the news latelya new study published in the journal Nature Medicine suggests that the L-carnitine, not the saturated fat, found in red meat is the real culprit in heart disease risk and that L-carnitine supplements are unsafe and have side effects. Folks, this is just the latest example of the pitfalls associated with mainstream media reporting and medical research.

First of all, the study authors state that gut bacteria convert carnitine into a compound called trimethylamine-N-oxide (TMAO), and they believe that TMAO allows cholesterol to build up in artery walls, thereby raising heart disease risk. However, even if carnitine is converted to TMAO, it is highly unlikely to be a primary player in red meat’s adverse health effects, as the researchers theorized. Here’s why.

A pound of steak contains approximately 400 mg of carnitine, some of which is likely converted to TMAO. But a pound of fish contains 1,700 mg of TMAO. So if TMAO is the real culprit then why is fish, which contains much more TMAO than what your body would convert from the L-carnitine found in red meat, universally accepted as being cardio-protective?

No Studied L-Carnitine Side Effects with Normal Usage

As for the suggestion that L-carnitine side effects are harmful, this is simply a matter of guilt by association. The researchers state that when mice were fed the human equivalent of 26,000 mg of carnitine per day, they developed arterial blockages—that equate to 26–52 times the normal supplement dose of 500–1,000 mg!

Furthermore, all of the news reports neglected to mention any of the previous human clinical trials and other studies that demonstrated carnitine’s significant benefits, including those studies using rabbits, which are considered to be the best model of human heart disease.

The bottom line: I stand by my recommendation of 500–1,000 mg of supplemental L-carnitine per day.

Now it’s your turn: Do you take L-carnitine supplements?

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DISCLAIMER: The content of is offered on an informational basis only, and is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified health provider before making any adjustment to a medication or treatment you are currently using, and/or starting any new medication or treatment. All recommendations are "generally informational" and not specifically applicable to any individual's medical problems, concerns and/or needs.

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