When Should You Take L Carnitine? MuscleTech L Carnitine: Benefits, Side Effects, FAQ, Sources, and Dosage L carnitine helps transport fatty acids into your cells' mitochondria, where they can be used for energy. That's why it's often marketed for fat loss and energy support. Common use: People usually take WHO SHOULD TAKE L CARNITINE L Carnitine is great for people looking to add an additional tool in their fat loss arsenal and is often times paired with a thermogenic. It can also