Well, yes, depending on what "heart healthy" means for you.

Carnitine doesn’t hurt, but it also doesn’t do much for us unless we are carnitine-deficient.

This is from the August 2000 issue of the American Journal of Cliical Nutrition:

"Available experimental clinical studies designed to assess the effect of carnitine on exercise metabolism or performance in healthy humans do not permit definitive conclusions to be drawn. In the aggregate, however, these studies suggest that carnitine supplementation does not improve maximal oxygen uptake or metabolic status during exercise in healthy humans. Carnitine administration for 1 mo in humans increases plasma carnitine concentrations but does not increase muscle carnitine content. Additional clinical trials integrating physiologic, biochemical, and pharmacologic assessments are needed to definitively clarify any effects of carnitine on exercise performance in healthy persons."

There’s not a lot of research going on into carnitine because it apparently doesn’t do much.

Now, what is it that concerns you about your heart? Atherosclerosis? Arrhythmia? You’d be ok with carnitine.

Carnitine wouldn’t cause these, and so is safe to take on these accounts. Carnitine doesn’t protect against them, either, so you wouldn’t want to try to take it to be protective.
It doesn’t cause edema, it doesn’t do much of anything bad.

The only caution that I know about is if you are on thyroid medication because carnitine can interfere with thyroid hormone. If you are low on that, you might not want to take carnitine.

Other than that, it’s harmless. It is pretty close to useless, because since 1996 we’ve known that it really doesn’t seem to increase athletic performance, but it’s harmless, which is a lot more than we can say for most supplements.
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