New study links L carnitine in red meat to heart disease Harvard Health L Carnitine: Benefits, Side Effects, FAQ, Sources, and Dosage When to take L carnitine: Dosage, forms, and side effects L Carnitine: Benefits, Uses, Side Effects, and More Losing weight with L carnitine supplements. Yes or no? L Carnitine doesnt magically burn fat, it helps your body use fat as energy. Combine it with training and consistency, and youll feel the difference @Marybosch shows us how L Carnitine will boost